Crowbook User Guide 0.15.0

Élisabeth Henry

Crowbook User Guide

Table of contents

Chapter 1

Travis status Appveyor status

Crowbook’s aim is to allow you to write a book in Markdown without worrying about formatting or typography, and let the program generate HTML, PDF and EPUB output for you. Its focus is novels and fiction, and the default settings should (hopefully) generate readable books with correct typography without requiring you to worry about it.

To see what Crowbook’s output looks like, you can read the Crowbook guide rendered in HTML, PDF or EPUB.

You can also play with the online demo version.

There are two ways to install Crowbook: either using precompiled binaries, or compiling it using cargo.

See the releases page to download a precompiled binary for your architecture (currently: Linux, Windows and MacOSX). Just extract the archive and run crowbook (or crowbook.exe on Windows). You might also want to copy the binary somewhere in your PATH for later usage.

If you are on Debian GNU/Linux or Ubuntu (on a PC architecture), you can also download .deb packages on the releases page.

Cargo is the package manager for Rust. You can install it here. Once that is done:

$ cargo install crowbook

will automatically download the latest crowbook release on, compile it, and install it on your system.

Some dependencies also require building C libraries; you might thus also need to install a C compiler and make/cmake build tools. You can also try to build a version of Crowbook without optional features: cargo install crowbook --no-default-features --features "clap" will disable syntactic highlighting and proofreading, requiring less dependencies.

While there should be, strictly speaking, no real dependencies to be able to run Crowbook (it is published as a statically compiled binary), some features require additional commands to work correctly:

  • EPUB rendering requires the zip command to be present on your system;

  • PDF rendering requires a working installation of LaTeX (preferably xelatex).

The simplest command is:

$ crowbook <BOOK>

where BOOK is a configuration file. Crowbook will parse this file and generate HTML, EPUB, and/or PDF output formats, according to the settings in the configuration file.

To create a new book, assuming you have a list of Markdown files, you can generate a template configuration file with the --create argument:

$ crowbook --create chapter_*.md

This will generate a default file, which you’ll need to complete. This configuration file contains some metadata, options, and lists the Markdown files.

For short books containing only a single Markdown file, it is possible to embed some metadata at the beginning of the file and use the --single or -s option to run crowbook directly on this Markdown file and avoid creating a separate book configuration file:

$ crowbook -s

For more information, see the chapters on the arguments supported by crowbook and on the configuration file.

Crowbook supports HTML, PDF and EPUB (either version 2 or 3) as output formats. See the Crowbook User Guide rendered in HTML, EPUB and PDF.

Crowbook uses pulldown-cmark and thus should support most of CommonMark Markdown. Inline HTML, however, is not implemented, and probably won’t be, as the goal is to have books that can also be generated in PDF (and maybe ODT).

Maybe the most specific “feature” of Crowbook is that it does its best to “clean” the input text before rendering it. By default, it removes superfluous spaces and tries to use curly quotes. If the book’s language is set to french, it also tries to respect french typography by replacing spaces with non-breaking ones when it is appropriate (e.g. before ‘?’, ‘!’, ‘;’ or ‘:’).

Please open an issue describing typographic rules if you want them to be implemented for other languages.

Crowbook tries to correctly translate local links in the input Markdown files: e.g. if you have a link to a Markdown file that is part of your book, it will be transformed into a link inside the document.

Crowbook supports inline YAML blocks:

author: Me
title: My title

This is mostly useful when Crowbook is run with the --single argument (receiving a single Markdown file instead of a book configuration file), for short texts that only contain one “chapter”.

Crowbook can also generate “proofreading” copies in HTML or PDF, highlighting grammar errors and repetitions. For more information, see the proofreading chapter of the guide.

Crowbook has experimental support for writing interactive fiction (only for HTML). For more information, read the interactive fiction chapter.

While the default settings will hopefully generate something that should look “good enough”, it is possible to customize the output, essentially by providing different templates.

See the issue tracker on GitHub.

Besides the Rust compiler and standard library, Crowbook uses the following libraries: pulldown-cmark, yaml-rust, mustache, clap, chrono, uuid, mime_guess, crossbeam, walkdir, rustc-serialize, caribon, hyper, url, lazy_static, regex, term, numerals, syntect.

It can also embed Highlight.js in HTML output to enable syntax highlighting for code blocks.

It also uses configuration files from rust-everywhere to use Travis and Appveyor to generate binaries for various platforms on each release.

While Crowbook directly doesn’t use them, there was also inspiration from Pandoc and mdBook.

Also, the W3C HTML validator and the IDPF EPUB validator proved to be very useful during development and testing.

See ChangeLog.

See how you can contribute to Crowbook.

If you find this project useful, you can also support its author by making a Paypal donation.

While the main purpose of Crowbook is to be run as a standalone program, the code is written as a library, so if you want to build on it you can use it as such. You can look at the generated documentation on

Note that, in order to facilitate code reuse, some features have been split to separate libraries:

  • epub-builder makes it easier to generate EPUB files.

  • crowbook-text-processing contains all the “typographic” functions (smart quotes, handling of non-breaking spaces in french, ...).

  • crowbook-intl is used for the internationalization (translation) process.

Crowbook is free software: you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License (LGPL), version 2.1 or (at your option) any later version. See LICENSE for more information.

Crowbook’s logo is licensed under the Creative Commons Attribution 4.0 International license, based on the Rust logo by Mozilla Corporation.

Crowbook includes binary (minified) CSS and Javascript files from Highlight.js, written by Ivan Sagalaev, see license

Chapter 2

Crowbook can take a number of arguments, generally in the form:

crowbook [OPTIONS] [BOOK]

The most important argument is obviously the book configuration file. It is mandatory in most cases: if you don’t pass it, crowbook will simply display an error. In a normal use case this is the only argument you’ll need to pass, as most options will be set in this configuration file.

It is, however, possible to pass more arguments to crowbook:


crowbook [BOOK] --create ...


crowbook [BOOK] -c ...

Creates a new book from a list of Markdown files. It will generate a book configuration file with all file names specified as chapters. It either prints the result to stdout (if BOOK is not specified) or generates the file BOOK (or abort if it already exists).

crowbook --create

will thus generate a file containing:

author: Your name
title: Your title
lang: en

## Output formats

# Uncomment and fill to generate files
# output.html: some_file.html
# output.epub: some_file.epub
# output.pdf: some_file.pdf

# Or uncomment the following to generate PDF, HTML and EPUB files based on this file's name
# output: [pdf, epub, html]

# Uncomment and fill to set cover image (for EPUB)
# cover: some_cover.png

## List of chapters


crowbook --create

will print the same result, but to stdout (without creating a file).


crowbook --single <FILE>


crowbook -s <FILE>

This argument allows you to give crowbook a single Markdown file. This file can contain an inline YAML block to set some book options. Inline YAML blocks must start and end with a line containing only --- (three dashes).


author: Joan Doe
title: A short story
output: [html, epub, pdf]

Content of the story in Markdown.

If this YAML block is not at the beginning of a file, it must also be preceded by a blank line.

This allows to not have to write a .book configuration file for a short story or an article. crowbook -s is rougly equivalent to having a book configuration file containing:


That is, the chapter heading (if any) won’t be displayed in the output documents (though they still appear in the TOC).

Note that by default, using --single or -s sets the default LaTeX class of the book to article instead of book.


crowbook <BOOK> --set [KEY] [VALUE]...

This argument takes a list of KEY VALUE pairs and allows setting or overriding a book configuration option. All valid options in the configuration files are valid as keys. For more information, see the configuration file.

$ crowbook --set tex.paper.size a4paper

will override the paper size for PDF generation.


crowbook --list-options


crowbook -l

Displays all the valid options that can be used, whether in a book configuration file, with --set, or in an inline YAML block.


crowbook --print-template <TEMPLATE>

Prints the built-in template to stdout. Useful if you want to customize the appearance of your document.

E.g., if you want to modify the CSS used for HTML rendering:

$ crowbook --print-template html.css > my_style.css
# edit my_style.css in your favourite editor
$ crowbook --set html.css my_style.css
# or add "html.css: my_style.css" in


crowbook --stats <BOOK>


crowbook -S <BOOK>

Display some statistics (word and character counts) about the book.


crowbook --proofread <BOOK>


crowbook -p <BOOK>

Equivalent to --set proofread true, enables proofreading. See Proofreading.


crowbook --autograph <BOOK>


crowbook -a <BOOK>

Prompts for a an autograph execution. This is a Markdown block that will be inserted at the beginning of the book.

$ crowbook --autograph
Enter autograph:
To my dear friend John,

Cheers, *Joan*

will add the block of text that was entered to all output files.


crowbook <BOOK> --verbose

If this flag is set, Crowbook will print more warnings it detects while parsing and rendering.


crowbook <BOOK> --to [FORMAT]


crowbook <BOOK> -t [FORMAT]

Generate only the specified format. FORMAT must be either epub, pdf, html, html.dir, odt or tex.

If an output file for the format is not specified in the book configuration file, crowbook will fail to render PDF, ODT and EPUB, whereas it will print HTML and TeX files on stdout. It is, however, possible to specify a file with the --output option.

crowbook --to html

will generate some HTML, and prints it either to the file specified by output.html in, or to stdout if it is not specified.

crowbook --to pdf --output foo.pdf

will generate a foo.pdf file.


crowbook <BOOK> --to <FORMAT> --output <FILE>


crowbook -t <FORMAT> -o <FILE> <BOOK>

Specifies an output file. Only valid when --to is used.


crowbook --lang <LANG>


crowbook -L <LANG>

Set the runtime language used by Crowbook. Currently, only a french translation is available. By default, Crowbook uses the LANG environment variable to determine which language to use, but this option allows to override it (e.g. for operating systems that don’t use such an option, such as Windows).

$ crowbook --lang fr --help

will display Crowbook’s help message in french.

Note that this argument has nothing to do with the lang option that you can set in the book configuration file, which specifies the language of the book. This argument specifies the language of the text messages that Crowbook will display while running, but has no effect on the generated documents.

Chapter 3
The configuration file

If you want to use Crowbook for your book, this configuration file is all you’ll have to add, beside the Markdown files containing the text of your book.

The format is not very complicated. This is an example of it:

# metadata
author: Joan Doe
title: Some book
lang: en

output: [html, pdf, epub]

# list of chapters

Basically, it is divided in two parts:

  • a list of options, under the form key: value, following YAML syntax.

  • a list of Markdown files.

Lines starting with the # characters are comments and are discarded.

Sometimes, you only have one Markdown file and might not want to have a separate configuration file. In this case, you can specify options at the beginning of your Markdown file, using an inline YAML block, separated by two lines containing only ---:

author: Joan Doe
title: Some (short) book
lang: en

output: [html, pdf, epub]

# Some (short) book

The book content, formatted in Markdown.

This method only allows to set up options: you can’t include a list of chapters in this way, since the only “chapter” that will be included is this Markdown file itself.

You can then use

crowbook -s

to generate output formats from this Markdown file.

By default (unless input.yaml_blocks is set to true), Crowboook will only read those inline blocks when it is runned with crowbook --single (or crowbook -s).

There are various options to include a Markdown file.

  • + includes a numbered chapter.

  • - includes an unnumbered chapter.

  • ! includes a chapter whose title won’t be displayed (except in the table of contents); this is useful for e.g. including a copyright at the beginning or the book, or for short stories where there is only one chapter.

  • 42. specifies the number for a chapter.

  • @ includes a part instead of a chapter.

So a typical usage might look like this:

0. # We want to start at chapter 0 instead of 1
# Next chapters can be numbered automatically

There are two important things to note:

  1. you must not use quotes around the file names.

  2. the paths of these files are relative to the directory where your configuration file is. This means you can run crowbook books/my_trilogy/first_book/ without being in the book’s directory.

Also note that you don’t have to specify a title. This is because the title of the chapter is inferred from the Markdown document. To go back to our previous example:


does not specify a chapter title, because it will read it directly in, e.g.:

# The day I was born #

Ideally, you should have one and only one level-one header (i.e. chapter title) in each Markdown file. If you have more than one, it might mess with the table of contents in some cases (e.g. for EPUB).

Parts are included using the @ character, followed by the same characters than for chapters:


However, you usually don’t really want to have a content directly below the part, only chapters (though it can be useful to add an introduction before the first chapter of this part), so there is also a more straighforward way to use parts, using only the @ character followed by the (markdown-formatted) title of this part:

@ Beginning
@ Middle
@ Appendix

With this shortcut, parts are always numbered.

If you write your book to be rendered by crowbook, it is better to have one Markdown file per chapter. It is, however, possible to work with divisions at lower levels. In order to properly include these files, you can use the following syntax:


Note that there isn’t different syntax for numbered or unnumbered sections/subsections: you can only change the numbering scheme at the chapter level.

When including those files, Crowbook will include them in the table of content as part of the previous chapter (or section for subsections, and so on). It will also adjust the header levels of the Markdown files, so, in the previous example, a level-1 header in will be displayed as a level-2 header in the book, and a level-1 header in as a level-3 header.

This can cause issues as only six levels of headers are supported; hence, if you include a level-5 header in, it will cause an error.

The first part of the configuration file is dedicated to pass options to Crowbook. This is YAML syntax, so each line should be of the form key: value. Note that in most cases you don’t have to put string in quotes, e.g.:

title: My title

It is however possible (and sometimes necessary) to escape some characters using quotes around strings:

title: "My: title!"

It is possible to use multiline strings with >- and then indenting the lines that are part of the string:

title: >-
author: Joan Doe

will set title to "A long title". See block literals in YAML for more information on the various way to insert multiline strings (which mostly change the way newlines will or won’t be inserted).

A final note on the syntax: all options must be set before the first chapter inclusion (that is, a line beginning with +, -, x. (where x is a number) or !).

Metadata are data about the book. Except for cover, which points to an image file, all its fields are strings. The main metadata are:

  • author

  • title

  • subtitle

  • lang, the language of the book. The unicode language code should be used, e.g. en_GB or en, fr_FR, or fr...

  • cover, a path to an image file for the cover of the book (not displayed in all output formats).

There are also additional metadata:

  • subject

  • description

  • license

  • version

  • date

You can define your own metadata by starting an option name with

All metadata are accessible from templates, see Templates.

The special import option allows you to include the options of another book configuration file. E.g., assuming that you want some common options to be applied to both and, you can create a file:

author: Joan Doe
lang: en
license: "Copyright (C) Joan Doe. All rights reserved."

html.header: "[Joan Doe's website]("
tex.template: my_template.tex

You can then include this file in

title: Foo


Or include it in, but override some of its features:

title: Bar
license: CC-BY-SA  # Override the license from


These options specify which files to generate.

Note that all file paths are relative to the directory where the configuration file is, not to the one where you run crowbook. So if you set:

output.epub: foo.epub

and run

$ crowbook some/dir/

foo.epub will be generated in some/dir, not in your current directory.

Crowbook will try to generate each of the files that are specified. That means that you’ll have to set at least one of those if you want a call to

$ crowbook

to generate anything. (It’s still possible to generate a specific format, and only this one, by using the --to and --output argument on the command line).

Note that some formats depend on some commands being installed on your system. Most notably, Crowbook depends on LaTeX (xelatex by default, though you can specify another command to use with tex.command) to generate a PDF file, so PDF rendering won’t work if it is not installed on your system. Crowbook also uses the zip command to generate the EPUB and ODT files.

Current output options are:

  • output.html: renders a standalone HTML file.

  • output.html.dir: renders a HTML directory with one page by chapter.

  • output.epub: renders an EPUB file.

  • output.tex: renders a LaTeX file.

  • output.pdf: renders a PDF file (using tex.command).

(There are other output options for generating proofreading files, see Proofreading, and interactive fiction, see Interactive fiction.)

Setting output file names manually can be a bit tedious, and is not always necessary. You can also specify a list of output formats with the output option:

output: [pdf, epub, html]

This is similar to the alternative syntax for YAML list:

  - pdf
  - epub
  - html

This option will set default output path for PDF, EPUB and HTML according to the book configuration file name. So, if your book is (or, it will generate my_book.pdf, my_book.html and my_book.epub.

You can also infer the output file name by specifying “auto” to e.g. output.html. The previous example is thus equivalent to

output.pdf: auto
output.epub: auto
output.html: auto

Additionally, the output.base_path option allows you to set where the output files will be written (relatively to the book configuration file). E.g.,

output.base_path: docs/book
output.epub: book.epub

will render the EPUB file in docs/book/book.epub.

Crowbook does its best to improve the typography of your text. Default settings should be good enough for most usages, but you can enable/disable specific options:

  • input.clean (default: true): if set to false, will disable all typographic “cleaning”. The algorithm is dependent on the language, though currently there is only a variant implemented for fr (french), dealing with the specific non-breaking spaces rules for this language.

  • input.clean.smart_quotes (default: true): if set to false, disable the “smart quote” feature, that (tries to) replace straight quotes with curly ones. As it is an heuristics and can’t be perfect, you might want to disable it in some circumstances.

  • input.clean.ligature_dashes (default: false): if set to true, will convert -- to en dash () and --- to em dash (). This can be useful if you want to use these characters but can’t access them easily on your keymap; however, as it can also cause problems if you do want to have two successive dashes, it is disabled by default.

  • input.clean.ligature_guillemets (default: false): is a similar feature for french ‘guillemets’, replacing << and >> to « and ».

These options allow to configure the rendering; they are used (or at least should be) for all formats.

  • rendering.highlight (default: syntect): specify if and how to perform syntax highlighting for code blocks. Valid values are:

    • syntect: uses the syntect library to perform syntax highlighting. This has the advantage of also enabling syntax highlighting for LaTeX/PDF and EPUB formats; however syntect support doesn’t seem to work on Windows.

    • highlight.js: this will use (and embed) highlight.js for HTML rendering, and will not perform any syntax highlighting for other output formats.

    • none: disable syntax highlighting.

If your version of crowbook (as is the case for Windows builds) isn’t built with syntect support, it will default to none if you try to use it.

  • rendering.highlight.theme: only used if rendering.highlight is set to syntect, selects the theme to use for syntax highlighting. Default is “InspiredGitHub”. Valid theme names are:

    • “InspiredGitHub”

    • “Solarized (dark)”

    • “Solarized (light)”

    • “base16-eighties.dark”

    • “base16-mocha.dark”

    • “base16-ocean.dark”

    • and “base16-ocean.light”.

  • rendering.num_depth: an integer that represents the maximum level of numbering for your book. E.g., 1 will only number chapters, while 2 will number chapters, sections, but not anything below that. 6 is the maximum level and turns numbering on for all headers. (Default is 1.) This also affects what levels will be displayed in the table of contents.

  • rendering.chapter and rendering.part: the strings that will be used to design chapter and part. E.g., if you want your parts to show as “Book III” instead of “Part III”, you can set rendering.part: Book.

  • rendering.part.roman_numerals and rendering.chapter.roman_numerals: these two booleans allow you to specify if you want roman numerals for part or chapter numbers (default is true for part numbers, and false for chapter numbers).

  • rendering.inline_toc: if set to true, Crowbook will include a table of contents at the beginning of the document.

  • the name of this table of contents as it should be displayed in the document.

  • rendering.initials: if set to true, Crowbook will use initials, or “lettrines”, displaying the first letter of each chapter bigger than the others.

  • rendering.part.reset_counter: set it to false if you don’t want your chapter numbers to start again at 1 at each part.

These options allow you to customize the HTML rendering (used both by the default HTML standalone renderer and the HTML multifile renderer):

  • html.icon: allows to set a favicon for the page.

  • html.header and html.footer: allow to set a custom (Markdown) string at the top and at the bottom of the HTML page. This is actually a template, so you can access metadata, such as {{{author}}}, {{{title}}}, or {{{version}}} in it. See the template chapter for more information on the fields you can use.

  • html.css: allows to set up a custom CSS file. You can also redefine the colors in a file and set it using html.css.colors.

  • html.css.add: allows you to add some specific lines of CSS in your book configuration file, that will be appended after the default CSS template.

  • html.highlight.theme: is similar to rendering.highlight.theme but only sets the theme for HTML output.

There are a few options specific to the standalone HTML renderer (default, set with output.html):

  • html.standalone.one_chapter: if set to true, will only display one chapter at a time (using Javascript), making it look similarly to the multifile HTML.

  • html.standalone.template: allows you to change or modify the HTML template for standalone HTML.

These options allow you to customize the LaTeX renderer (and, thus, the generated PDF documents):

  • tex.template: specifies a different LaTeX template.

  • tex.class: changes the LaTeX class used.

  • tex.paper.size and tex.font.size: (default a5paper and 10pt) allows to modify the page and font size.

  • tex.margin.left, tex.margin.right, and tex.margin.bottom: specify the margin of the page.

  • tex.links_as_footnotes: can be set to false if you don’t want links to also appear as footnotes (which means losing them if it is actually printed).

  • tex.highlight.theme: similar to rendering.highlight.theme, but only sets the theme for LaTeX/PDF rendering.

There are also options specific to the EPUB format:

  • epub.version: can be set to 2 or 3 (default 2).

  • epub.css: can be useful if you want to specify a customized stylesheet.

  • epub.highlight.theme: similar to rendering.highlight.theme but only sets a theme for EPUB output.

These options allow to embed additional files for some formats (currently, only EPUB). This can be useful for embedding fonts.

A list of files or directories that should be added.

resources.files: [font1.otf, font2.otf]

It is also possible to specify a directory (or multiple directories). So if you have a fonts directories containing font1.otf and font2.otf,

resources.files: [fonts]

will be equivalent to:

resources.files: [fonts/font1.otf, fonts/font2.otf]

default: not set

This option determine where (in which directory), in the resulting document, those files will be copied. The default is data, so by default the resources.files in the first example above will search font1.otf and font2.otf in the same directory than the .book file, and will copy them to data/font1.otf and data/font2.otf in the EPUB file. This is therefore this last path that you should use if you want to access those files e.g. in a custom CSS stylesheet.

Note that if you pass directories to resources.files, the whole directory would be copied. So assuming fonts/ contains font1.otf and font2.otf

resources.files: [fonts]
resources.path: data

will copy these two files to data/fonts/font1.otf and data/fonts/font2.otf (and not data/font1.otf and data/font2.otf).

Similarly, the whole path of resources.files is copied, so

resources.files: [fonts/font1.otf, fonts/font2.otf]

will yield the same result.

default: data

Here is the complete list of options. You can always look at it by running crowbook --list-options or crowbook -l.

Note that these options have a type, which in most case should be pretty straightforward (a boolean can be true or false, an integer must be composed by a number, a string is, well, any string (note that you might need to use quotes if it includes some characters that may lead the YAML parser to read it as an array, an integer or a list), and a list of strings is a list containing only strings, see YAML syntax). The path type might puzzle you a bit, but it’s equivalent to a string, except Crowbook will consider it relatively to the book file. The template path type is just the path of a template. Metadata are just strings.

  • type: metadata

  • default value: ""

  • Author of the book

  • type: metadata

  • default value: ""

  • Title of the book

  • type: metadata

  • default value: en

  • Language of the book

  • type: metadata

  • default value: not set

  • Subject of the book (used for EPUB metadata)

  • type: metadata

  • default value: not set

  • Description of the book (used for EPUB metadata)

  • type: path

  • default value: not set

  • Path to the cover of the book

  • type: metadata

  • default value: not set

  • Subtitle of the book

  • type: metadata

  • default value: not set

  • License of the book. This information will be displayed on PDF documents

  • type: metadata

  • default value: not set

  • Version of the book

  • type: metadata

  • default value: not set

  • Date the book was revised

  • type: list of strings

  • default value: not set

  • Specify a list of output formats to render

  • type: path

  • default value: not set

  • Output file name for EPUB rendering

  • type: path

  • default value: not set

  • Output file name for HTML rendering

  • type: path

  • default value: not set

  • Output directory name for HTML rendering

  • type: path

  • default value: not set

  • Output file name for LaTeX rendering

  • type: path

  • default value: not set

  • Output file name for PDF rendering

  • type: path

  • default value: not set

  • Output file name for ODT rendering

  • type: path

  • default value: not set

  • Output file name for HTML (interactive fiction) rendering

  • type: path

  • default value: ""

  • Directory where those output files will we written

  • type: string

  • default value: syntect

  • If/how highligh code blocks. Possible values: “syntect” (default, performed at runtime), “highlight.js” (HTML-only, uses Javascript), “none”

  • type: string

  • default value: InspiredGitHub

  • Theme for syntax highlighting (if rendering.highlight is set to ‘syntect’)

  • type: boolean

  • default value: false

  • Use initials (‘lettrines’) for first letter of a chapter (experimental)

  • type: boolean

  • default value: false

  • Display a table of content in the document

  • type: string

  • default value: "{{{loc_toc}}}"

  • Name of the table of contents if it is displayed in document

  • type: integer

  • default value: 1

  • The maximum heading levels that should be numbered (0: no numbering, 1: only chapters, ..., 6: all)

  • type: string

  • default value: not set

  • How to call chapters

  • type: string

  • default value: not set

  • How to call parts (or ‘books’, ‘episodes’, ...

  • type: boolean

  • default value: false

  • If set to true, display chapter number with roman numerals

  • type: boolean

  • default value: true

  • If set to true, display part number with roman numerals

  • type: boolean

  • default value: true

  • If set to true, reset chapter number at each part

  • type: string

  • default value: "{{{number}}}. {{{chapter_title}}}"

  • Naming scheme of chapters, for TOC

  • type: string

  • default value: "{{{number}}}. {{{part_title}}}"

  • Naming scheme of parts, for TOC

  • type: path

  • default value: not set

  • Import another book configuration file

  • type: path

  • default value: not set

  • Path to an icon to be used for the HTML files(s)

  • type: string

  • default value: not set

  • If set, set theme for syntax highlighting for HTML output (syntect only)

  • type: string

  • default value: not set

  • Custom header to display at the beginning of html file(s)

  • type: string

  • default value: not set

  • Custom footer to display at the end of HTML file(s)

  • type: template path

  • default value: not set

  • Path of a stylesheet for HTML rendering

  • type: string

  • default value: not set

  • Some inline CSS added to the stylesheet template

  • type: template path

  • default value: not set

  • Path of a stylesheet for the colors for HTML

  • type: template path

  • default value: not set

  • Path of a javascript file

  • type: template path

  • default value: not set

  • Path of a media print stylesheet for HTML rendering

  • type: template path

  • default value: not set

  • Set another highlight.js version than the bundled one

  • type: template path

  • default value: not set

  • Set another highlight.js CSS theme than the default one

  • type: boolean

  • default value: false

  • Display footnotes as side notes in HTML/Epub (experimental)

  • type: boolean

  • default value: true

  • Replace unicode non breaking spaces with HTML entities and CSS

  • type: string

  • default value: "<h1 id = 'link-{{{link}}}'>{{#has_number}}<span class = 'chapter-header'>{{{header}}} {{{number}}}</span>{{#has_title}}<br />{{/has_title}}{{/has_number}}{{{title}}}</h1>"

  • Inline template for HTML chapter formatting

  • type: string

  • default value: "<h2 class = 'part'>{{{header}}} {{{number}}}</h2> <h1 id = 'link-{{{link}}}' class = 'part'>{{{title}}}</h1>"

  • Inline template for HTML part formatting

  • type: template path

  • default value: not set

  • Path of an HTML template for standalone HTML

  • type: boolean

  • default value: false

  • Display only one chapter at a time (with a button to display all)

  • type: template path

  • default value: not set

  • Path of a javascript file

  • type: template path

  • default value: not set

  • Path of a HTML template for multifile HTML

  • type: template path

  • default value: not set

  • Path of a javascript file

  • type: string

  • default value: not set

  • Javascript code that will be run at the beginning of each segment

  • type: string

  • default value: not set

  • Javascript code that will be run at the end of each segment

  • type: template path

  • default value: not set

  • Javascript code that will be run at the beginning of a ‘game’

  • type: integer

  • default value: 2

  • EPUB version to generate (2 or 3)

  • type: string

  • default value: not set

  • If set, set theme for syntax highlighting for EPUB output (syntect only)

  • type: template path

  • default value: not set

  • Path of a stylesheet for EPUB

  • type: string

  • default value: not set

  • Inline CSS added to the EPUB stylesheet template

  • type: template path

  • default value: not set

  • Path of an xhtml template for each chapter

  • type: boolean

  • default value: true

  • Add ‘Title’ and (if set) ‘Cover’ in the EPUB table of contents

  • type: boolean

  • default value: true

  • Replace unicode non breaking spaces with HTML entities and CSS

  • type: string

  • default value: not set

  • If set, set theme for syntax highlighting for LaTeX/PDF output (syntect only)

  • type: boolean

  • default value: true

  • Add foontotes to URL of links so they are readable when printed

  • type: string

  • default value: xelatex

  • LaTeX command to use for generating PDF

  • type: template path

  • default value: not set

  • Path of a LaTeX template file

  • type: string

  • default value: not set

  • Inline code added in the LaTeX template

  • type: string

  • default value: book

  • LaTeX class to use

  • type: string

  • default value: a5paper

  • Specifies the size of the page.

  • type: string

  • default value: not set

  • Specifies left margin (note that with book class left and right margins are reversed for odd pages, thus the default value is 1.5cm for book class and 2cm else)

  • type: string

  • default value: not set

  • Specifies right margin(note that with book class left and right margins are reversed for odd pages, thus the default value is 2.5cm for book class and 2cm else)

  • type: string

  • default value: "2cm"

  • Specifies top margin

  • type: string

  • default value: "1.5cm"

  • Specifies left margin

  • type: boolean

  • default value: true

  • If true, generate a title with \maketitle

  • type: integer

  • default value: not set

  • Specify latex font size (in pt, 10 (default), 11, or 12 are accepted)

  • type: boolean

  • default value: true

  • If disabled, don’t try to find references inside the document

  • type: boolean

  • default value: false

  • If set to true, use ‘stdpage’ package to format a manuscript according to standards

  • type: list of strings

  • default value: not set

  • Whitespace-separated list of files to embed in e.g. EPUB file; useful for including e.g. fonts

  • type: path

  • default value: data

  • Paths where additional resources should be copied in the EPUB file or HTML directory

  • type: path

  • default value: not set

  • Path where to find resources (in the source tree). By default, links and images are relative to the Markdown file. If this is set, it will be to this path.

  • type: path

  • default value: not set

  • Set base path but only for links. Useless if resources.base_path is set

  • type: path

  • default value: .

  • Set base path but only for images. Useless if resources.base_path is set

  • type: path

  • default value: .

  • Set base path but only for additional files. Useless if resources.base_path is set.

  • type: path

  • default value: .

  • Set base path but only for templates files. Useless if resources.base_path is set

  • type: boolean

  • default value: true

  • Toggle typographic cleaning of input markdown according to lang

  • type: boolean

  • default value: true

  • If enabled, tries to replace vertical quotations marks to curly ones

  • type: boolean

  • default value: false

  • If enabled, replaces ‘--’ to en dash ('–') and ‘---’ to em dash ('—')

  • type: boolean

  • default value: false

  • If enabled, replaces ‘<<’ and ‘>>’ to french “guillemets” ('«’ and ‘»’)

  • type: boolean

  • default value: false

  • Enable inline YAML blocks to override options set in config file

  • type: boolean

  • default value: true

  • Consider HTML blocks as text. This avoids having <foo> being considered as HTML and thus ignored.

  • type: boolean

  • default value: false

  • If enabled, allow support for superscript and subscript using respectively fooup and bardown syntax.

  • type: path

  • default value: (empty string)

  • Path where to create a temporary directory (default: uses result from Rust’s std::env::temp_dir())

  • type: string

  • default value: zip

  • Command to use to zip files (for EPUB/ODT)

  • type: path

  • default value: not set

  • Output file name for HTML rendering with proofread features

  • type: path

  • default value: not set

  • Output directory name for HTML rendering with proofread features

  • type: path

  • default value: not set

  • Output file name for PDF rendering with proofread features

  • type: boolean

  • default value: false

  • If set to false, will disactivate proofreading even if one of output.proofread.x is present

  • type: boolean

  • default value: false

  • If true, try to use language tool server to grammar check the book

  • type: integer

  • default value: 8081

  • Port to connect to languagetool-server

  • type: boolean

  • default value: false

  • If true, try to use grammalecte server to grammar check the book

  • type: integer

  • default value: 8080

  • Port to connect to grammalecte server

  • type: boolean

  • default value: false

  • If set to true, use Caribon to detect repetitions

  • type: integer

  • default value: 25

  • Max distance between two occurences so it is considered a repetition

  • type: boolean

  • default value: true

  • Enable fuzzy string matching

  • type: float

  • default value: 0.2

  • Max threshold of differences to consider two strings a repetition

  • type: boolean

  • default value: true

  • Ignore proper nouns for repetitions

  • type: float

  • default value: 2.0

  • Threshold to detect a repetition

Chapter 4
Markdown format

crowbook uses pulldown-cmark, which is an implementation of CommonMark, so for more information on Markdown syntax, you can refer to those websites.

However, pulldown-cmark also implements a handful of unofficial extensions, and crowbook also adds its own variants, so there are a few syntax elements that are not covered by the CommonMark reference.

Tables can be included in your Markdown file.


|        Author      |   Book                     |
| Anne Rice          | Interview With the Vampire |
| Terry Pratchett    | Hogfather                  |
| George Martin      | A Dance with Dragons       |

will render as

Anne RiceInterview With the Vampire
Terry PratchettHogfather
George MartinA Dance with Dragons

Crowbook doesn’t currently support specifying column alignment.

Footnotes can be specified the following way:

Footnotes can be useful[^1] and make you look clever.

[^1]: But you shouldn't use them too much.

Will be rendered as:

Footnotes can be useful[^1] and make you look clever.

You can use multiple paragraphs in a footnote definition. This can sometimes be useful, but it can also be tricky, as if you only let an empty line before the next paragraph, it will also be included in the footnote. And probably the next one and the following one too:

This is a footnote usage[^1].

[^1]: This is obviously part of the footnote definition.

This is less obviously ALSO part of the footnote definition.

This is NOT part of the foonote.

Due to its own quirks, crowbook will duplicate footnotes if you reference them multiple times:

This footnote is unique[^2] but referenced twice[^2].

[^2]: Or is it?

This footnote is unique[^2] but referenced twice[^2].

Crowbook v0.12.0 added experimental support for superscript and subscript, using respectively foo^up^ and bar~down~ syntax, which will render as “fooup" and “bardown“; this feature is quite a hack above the Markdown parsing library, and as such might cause issue if you mix it with other Markdown syntax elements (or, in the previous example, for smart quote detection). This is why you’ll need to enable it with crowbook.mardown.superscript.

This is not per se a new syntactic element, but Crowbook distinguish two kind of images, according to their position in the document:

  • standalone images, which are the only elements of a paragraph;

  • inline images, which are placed in a container containing other elements.

Standalone images will typically be resized to fill the width of the page, while inline images are not resized.

This image is on its own paragraph, and thus considered “standalone” and resized to fit width:


While this one Logo is embedded in a paragraph and its size is unchanged.

crowbook also adds some syntax for interactive fiction, to make embedding Javascript code easier. It is only enabled for the interactive fiction renderer. For more information, see the chapter on this matter.

Chapter 5

Crowbook allows the user to specify a number of templates.[^1]

Each of this template can be overriden by a custom one, by setting e.g.:

html.css: my_template.css

in the book configuration file. The templates that you are most susceptible to modify are the following:

  • html.css: stylesheet for HTML output;

  • epub.css: stylesheet for EPUB output;

  • tex.template: template of a LaTeX file.

Except for inline templates, which are set directly in the book configuration file:

# Template that modify how a chapter title is displayed
rendering.chapter.template: "{{{loc_chapter}}} {{{number}}}: {{{chapter_title}}}"

# CSS code added to default CSS templates (but don't override it)
html.css.add: "h1 { background-color: red; }"
epub.css.add: "h1 { background-color: gray; }"

# LaTeX code added to default LaTeX template (but doesn't override it)
template.tex.add: "\usepackage{libertineotf}"

most templates must be in a separate file:

tex.template: my_template.tex

The easiest way to create a new template is to start with the default one. In order to do so, you can use the --print-template argument:

$ crowbook --print-template tex.template > my_template.tex

In order to get the chapter.xhtml template for EPUB3, you’ll also have to use --set epub.version 3:

$ crowbook --print-template epub.chapter.xhtml --set epub.version 3 > my_epub3_template.xhtml

Crowbook uses rust-mustache as its templating engine, which allows to use Mustache syntax in the templates.

It mainly boils down to using {{{foo}}}[^2] to insert the value of variable foo in the document:

<h1 class = "title" >{{{title}}}<h1>
<h2 class = "author">{{{author}}}</h2>

Mustache also provides the possibility of checking whether a variable is set:

Foo exists
Foo does not exist

Crowbook uses this and sets some variables to true to allow templates to conditionally include some portions. E.g., in html.css:

/* Make list displays '–' instead of bullets */
ul li {
    list-style-type: '';
    padding-left: .5em;

In this case, Crowbook sets a variable whose name is equal to lang_foo to true, allowing to have different styles for some elements according to the language.

For more information about Mustache syntax, see the Mustache manual.

Since LaTeX already uses a lot of curly brackets, the default template sets an altenative syntax to access variables, with <<&foo>>[^3]:

  1. escaping is already done by Crowbook before setting variable content;

  2. escaping HTML in a LaTeX document won’t probably look good.

The javascript file used by both the standalone HTML renderer and the multiple files HTML renderer.

This is not currently an actual template, just a plain javascript file which cannot contain mustache tags.

The main CSS file used by both the standalone HTML renderer and the multiple files HTML renderer.

A CSS file containing only colour settings. Used by html.css.

This is not currently an actual template, just a plain CSS file which cannot contain mustache tags.

An additional CSS file used by both the standalone HTML renderer and the multiple files HTML renderer. Its purpose is to provide CSS instructions for printing (i.e., when the user clicks the print button in her browser).

This is not currently an actual template, just a plain CSS file which cannot contain mustache tags.

A javascript file used by both HTML renderers to highlight codes in code blocks. It should be a variant of highlight.js.

This is not an actual template, just a plain javascript file.

A CSS file used by both HTML renderers to set the theme of highlight.js. It should, though, be an highlight.js theme.

This is not an actual template, just a plain CSS file.

A javascript file used only by the standalone HTML renderer. Its main purpose is to handle the displaying of a single chapter at a time when one_chapter is set to true.

The main HTML template for standalone HTML renderer.

The main HTML template for multiple files HTML renderer.

The main (and currently only) template used by the LaTeX renderer.

This template is the main template used by the Epub renderer. It contains the XHTML template that will be used for each chapter.

This template is used by the Epub renderer and contains the style sheet.

Crowbook also has some inline templates, that are set in the book configuration file:

  • tex.template.add, html.css.add and epub.css.add allow to specify some LaTeX or CSS code directly in the book configuration file. This code will be added respectively to tex.template, html.css or epub.css template. For CSS templates, this code is inserted at the end of the template (allowing to redefine rules that are set by the template); for the LaTeX template, the code is inserted at the end of the preambule, just before the \begin{document} tag, allowing to redefine commands.

  • sets the name of the inline table of content, if it is displayed. By default, is is set to {{{loc_toc}}}, that is, a localised version of “Table of Contents”.

  • rendering.chapter.template sets the naming scheme for chapters, while rendering.part.template does the same for part. These are used only for text-only output, such as in the TOC. html.chapter.template and html.part.template allow to change the HTML formatting for parts and chapters. These options should probably only be used if you know what you’re doing, as they can break the document. If you only need to change the name of chapters or parts, use rendering.part and rendering.chapter instead.

For every template, Crowbook exports all of the metadata:

  • author;

  • title;

  • subtitle;

  • lang;

  • subject;

  • description;

  • license;

  • version;

  • date;

  • any option defined in the book configuration file will also be exported as metadata_foo.

These metadata can contain Markdown, which will be rendered. E.g., setting date: "20th of **september**" will render september in bold, using <b> tag for HTML or \textbf for LaTeX. If you need to use these data in places that don’t support formatted text (e.g. in meta tags), you can use the raw content by accessing xxx_raw instead (e.g., author_raw, title_raw, ...). (Note that the content of the raw metadata is not HTML-escaped, so in this case you might want to use {{xxx_raw}} instead of {{{xxx_raw}}}.)

For each metadata foo that is set, Crowbook also inserts a has_foo bool set to true. This allows to use Mustache’s section for some logic, e.g.:

{{#has_version}}, version {{{version}}}{{/has_version}}

will avoid rendering “, version” when version is not set.

For all templates, Crowbook also exports some localisation strings loc_foo. They currently include:

Localisation keyValue in english
loc_tocTable of contents
loc_display_allDisplay all chapters
loc_display_oneDisplay one chapter

Crowbook also exports some additional fields for some templates, see below.

Mustache tagValueAvailable in...
contentA rendered version of the book or chapter’s contenthtml.standalone.template, html.dir.template, tex.template, epub.chapter.xhtml
tocA rendered version of the table of contentshtml.standalone.template, html.dir.template
has_tocSet to true if the table of contents is not emptyhtml.standalone.template
colorsThe content of html.css.colorshtml.css
footerThe content of html.footerhtml.standalone.template, html.dir.template
headerThe content of html.headerhtml.standalone.template, html.dirtemplate
scriptThe javascript file for this HTML documenthtml.standalone.template, html.dir.template
styleThe CSS file for this HTML document, that is, a rendered version of html.csshtml.standalone.template
A variable whose name corresponds to lang in book options (e.g. lang_en if lang is set to “en”, lang_fr if it is set to “fr”, ...)truehtml.css, epub.css
chapter_titleThe title of current chapterhtml.dir.template, epub.chapter.xhtml, rendering.chapter.template
chapter_title_rawThe title of current chapter (raw text without HTML formatting)html.dir.template, epub.chapter.xhtml, rendering.chapter.template
json_dataContains structured data with book’s metadata in JSON-LD formathtml.standalone.template, html.dir.template
highlight_codeTrue if html.highlight_code is truehtml.standalone.template, html.dir.template
highlight_cssThe content of html.highlight.csshtml.standalone.template
highlight_jsThe base64-encoded content of html.highlight.jshtml.standalone.tempate
common_scriptThe content of html.jshtml.single.js
one_chapterTrue if html.standalone.one_chapter is true, else not presenthtml.standalone.template, html.standalone.js
book.svgThe base64-encoded image of the button to display all chaptershtml.standalone.js, html.standalone.template
pages.svgThe base64-encoded image of the button to display one chapter at a timehtml.standalone.js, html.standalone.template
faviconThe <link rel = "icon" ...> tag if html.icon is sethtml.standalone.template, html.dir.template
menu_svgThe base64-encoded image of the hamburger menu imagehtml.standalone.template
prev_chapterTitle and a link of previous chapterhtml.dir.template
next_chapterTitle and a link of nexts chapterhtml.dir.template
classThe content of tex.classtex.template
bookTrue if tex.class is book, not set elsetex.template
tex_langThe babel equivalent of langtex.template
tex_titleSet to true to run \maketitletex.template
tex_sizeThe font size to pass to the LaTeX classtex.template
has_tex_sizeSet to true if tex_size is settex.template
margin_left, margin_right, margin_top, margin_bottomThe margins of the documenttex.template
initialsTrue if rendering.initials is true, not set elsetex.template
additional_codeSet to the content of tex.template.add, html.css.add or epub.css.addtex.template, html.css, epub.css

Chapter 6
Proofreading with Crowbook

Crowbook includes some proofreading features, that can be enabled if you set one of the

  • output.proofread.html

  • output.proofread.html_dir

  • output.proofread.pdf

output files (or include proofread.pdf in the list of formats to render to output). This allows you to generate different files for publishing and proofreading (you probably don’t want to publish a version that highlights your grammar errors or your repetitions).

Current proofreading features are:

  • repetition detection;

  • grammar check.

Since proofreading can take quite a lot of time, particularly for a long book, it is disabled by default. You’ll have to run:

$ crowbook --proofread


$ crowbook -p

to generate proofreading copies. Alternatively, if you want it to be activated each time you run crowbook on this book (which is not recommanded for long books, particularly if you want to perform a grammar check), you can set:

proofread: true

in the book configuration file.

Repetition detection is enabled with:

proofread.repetitions: true

It uses Caribon library to detect the repetition in your text. Since the notion of a repetition is relatively arbitrary, it is possible to adapt the settings. Default are:

# The maximum distance between two identical words to
# consider them a repetition
proofread.repetitions.max_distance: 25
# The minimal number of occurences to consider it a repetition
proofread.repetitions.threshold: 2.0
# Ignore proper nouns (words starting by a capital,
# not at a beginning of a sentence)
proofread.repetitions.ignore_proper: true

# Activate fuzzy string matching
proofread.repetitions.fuzzy: true
# The maximal ratio of difference to consider
# that two words are identical
# (E.g., with 0.2, "Rust" and "Lust" won't be
# considered as the same word, but they will be with 0.5)
proofread.repetitions.fuzzy.threshold: 0.2

For more information, see Caribon’s documentation.

Currently, repetitions are not displayed in PDF proofreading output.

Crowbook can use LanguageTool to detect grammar errors in your text. It is, however, a bit more complex to activate.

First, you’ll have to activate this feature in your book configuration file:

# Activate language tool support
proofread.languagetool: true
# (Optional) Sets the port number to connect to (default below)
proofread.languagetool.port: 8081

You’ll then have to download the stand-alone version of LanguageTool. It includes a server mode, which you’ll have to launch:

$ java -cp languagetool-server.jar org.languagetool.server.HTTPServer --port 8081

You can also use the LanguageTool GUI (languagetool.jar) and start the server from the menu “Text Checking -> Options”. This also allows you to configure LanguageTool more precisely by activating or deactivating rules.

You can then run Crowbook, and it will highlight grammar errors in HTML or PDF proofreading output files.

Note: running a grammar check on a long book (like a novel) can take up to a few minutes.

Grammalecte is a grammar checker specialized for the french language. If the language of your book is french, you can use it in a similar fashion to languagetool:

# Activate grammalecte support
proofread.grammalecte: true
# (Optional) Sets the port number to connect to (default below)
proofread.grammalecte.port: 8080

You’ll also need to run the Grammalecte server. First download the CLI and server version, then:

$ python3

You can then run Crowbook with --proofread to check the grammar of your book. It is possible to run both LanguageTool and Grammalecte on the same book (though might take a while for a long book...).

Chapter 7
Interactive fiction

Version v0.12.0 added experimental support for writing interactive fiction.

Since this support is experimental, it means it can change at anytime, and there is no guarentee that the interactive fiction you write for the current version of crowbook will work with the next release, even if it isn’t a major release.

If you want to have a non-linear story, you can simply use Markdown links just as you would for any other link:

* [Open the treasure chest](
* [It might be trapped, stay away from it](

All crowbook renderers should render this correctly, allowing the reader to “choose her adventure”. Note, however, that you still need to include all these Markdown files in you book configuration files.

While the above allows you to generate correct EPUB and PDF files, it will still display all the content if the reader chooses to read your book linearly. While this may not be a problem, you might want to only display the part of the book that the reader is actually exploring.

In order to do so, you can use the interactive fiction html renderer:

output.html.if: my_book.html

This output is similar to the standalone HTML output, except the option to display only a chapter at a time is always true, and there is no way to display the table of contents.

While the above allows the reader to choose his own path, its interactivity is quite limited. With the interactive fiction renderer, it is possible to include Javascript code in your Markdown files, using a code block element:

You open the chest, and you find a shiny sword. Yay!

    user_has_sword = true;

This Javascript code can return a string value, which will be displayed inside the document according to the reader’s previous choices:

You encounter a goblin, armed with a knife!

    if (user_has_sword) {
	    return "You kill him with your sword, congratulations!";
	} else {
	    return "You don't have any weapon, you die :(";

Note that only the interactive fiction renderer supports this way of embedding Javascript code. If you try to render a document containing such code blocks to EPUB, PDF, or the “normal” HTML renderer, they will be displayed as regular code blocks.

If you want to include Markdown formatting in the Javascript code (to display a passage or another without having to write HTML code), you can use the @"..."@ syntax:

    @"You face a troll!"@
    if (user_has_sword) {
	    @"* [Attack him with your sword]("@
	} else {
        @"* [Better run away]("@

Note that in this case you don’t need to return a value, this is done behind your back. Similarly, @"..."@ blocks don’t require semicolons.

If you need to access the value of a Javascript variable inside this Markdown code, you can use the {{...}} syntax:

    var name = prompt("Enter your name", "world");
	@"Hello, {{name}}"@

Sometimes, you want some text (or Javascript code) to only be displayed (or run) when the reader reads this passage the first time, or alternatively when she goes back to it. While it is trivial to add some code to check that, it is a common enough pattern to justify its own variant: you’ll juste have to insert a named code block with the number:

@"Only displayed at first passage"@

@"Only displayed at second passage"@

@"Displayed at passage 3, 4 and so on.

As other renderers, there are options specific to the interactive fiction.

html.if.new_game allows you to specify the path to a Javascript that will be run at the beginning of the game. Since this code is not embedded in a function and is at the root (and the beginning) of the document, it is a good place to declare all the functions and the global variables you might need for your interactive fiction mechanics.


html.if.new_game: some_file.js

html.if.new_turn and html.if.end_turn allow you to specify some Javascript code that will be executed at the beginning and the end of each segment. Unlike html.if.new_game, the (usually shorter) code is specified inline, and can return a string value that will be displayed at the beginning and the end of each segment. This is exactly like including code blocks at the beginning or the end of each of your Markdown file. E.g.:

html.if.new_turn: "nb_turns += 1;"
html.end_turn: "return 'Turn: ' + nb_turns;"

html.if.script allows you to specify the name of a Javascript file to override the default script.

Chapter 8
Tips and tricks

If you use Emacs as a text editor, there is a nice Markdown mode to edit Markdown files.

It is possible to use Crowbook for HTML previewing in this mode, which requires only minimal configuration and tweaking:

 '(markdown-command "crowbook - -qs  --to html --output -"))

You can then use markdown-preview (or C-c C-c p) to run Crowbook on this file and preview it in your browser. Or run markdown-live-preview-mode to see a live preview (updated each time you save your file) in Emacs’ integrated browser.

We set markdown-command to crowbook, the reason for this is a bit obvious. The arguments we give to crowbook might be a bit less obvious:

  • the fist argument, -, is actually the book file: it tells crowbook to read it from standard input.

  • -qs or --quiet --single tells Crowbook that is a a standalone markdown file, and not a book configuration file, and to be a bit quiet on error/info messages;

  • --to html specifies that HTML must be generated;

  • --output - tells Crowbook to display the result on the stdout, even if you set output.html to some_file.html.

In order to embed fonts in an EPUB file, you’ll first have to edit the stylesheet, which you can first obtain with:

$ crowbook --print-template epub.css > my_epub_stylesheet.css

You’ll need to use the @font-face attribute:

@font-face {
  font-family: MyFont;
  src: url(data/my_font.ttf);

Then you can add my_font.ttf to the files that need to be added to the EPUB zip file:

title: My Book
author: Me

cover: cover.png
output.epub: book.epub

resources.files: [my_font.ttf]

(Note that you’ll have to repeat the process for the different font-weight and font-style variants of your font if you want it to display correctly when there is some text in bold, italics, or both.)

Chapter 9

crowbook is a free software, and you can contribute to it. There are some things that can be accessible even if you don’t know anything about programming.

crowbook aims to support multiple languages. However, unfortunately, currently only English, French, and (in a more limited way) Spanish are currently supported. If you want to have better support for the language you write in, there are easy things you can do:

  • Provide a translation for the few strings that Crowbook insert into the rendered documents. This is really easy, as there are currently less than a dozen of them, and you just need to create a new variant of the ./lang/en.yaml file.

  • Open an issue about the typographic rules in your language, if crowbook doesn’t cover them.

  • Provide a translation for the crowbook program. It requires creating a variant of the .po file, which is a bit more work because (at this time) it’s around 1,500 lines (and less a priority than the first item of this list, as this translation only affects the the command-line interface and not the rendered documents).


  • html.css.colours has been renamed html.css.colors

  • Fixed issue with table of contents page numbers in PDF output

  • Fixed issue with invalid XHTML in EPUB when using description terms

  • Fixed left/right margins in LaTeX (which were reversed)

  • LaTeX outputs of french documents now use enspaces and narrow non-breaking spaces

  • New option:

    • tex:escape_nb_spaces defaults to true and will uses TeX codes to display non-breaking spaces.

  • Moved from pulldown-cmark to comrak for parsing Markdown. This may have some performances drawbacks but allows for a few more features:

    • Description lists

    • Strikethrough

    • Task items

  • New option:

    • crowbook.files_mean_chapters allow to enforce that each files means a chapter break or to make sure that it doesn’t (by default, only true for numbered chapters).

  • Fallback on Rust zip library when there is no zip command.

  • By default, don’t add an empty chapter title for non numbered “chapters” that don’t contain a title.

  • Now uses reqwest instead of hyper to connect to languagetool/grammalecte.

  • hyphenation dependency is now optional.

  • Dependencies update.

  • Fix type deduction issues for new rustc compliler

  • --stats can now display more statistics when used with the --verbose option (if support for advanced statistics is compiled)

  • LaTeX outputs now make uses of user-defined rendering.chapter and rendering.part

  • Dependencies update

  • New option:

    • autograph is an autograph added after title.

  • User interface:

    • new argument --autograph prompts for an autograph.

    • --list-options and --stats now use colors if available.

    • options description with --list-options are now wrapped.

  • Bugfixes:

    • Preserve errors/warnings order with fancy UI.

    • Clean secondary bar when there is an error instead of hanging the UI.

    • LaTeX: fancy headers only applies to fancy pages (not chapter pages).

  • Bugfixes:

    • EPUB: escape quotes in content.opf.

    • LaTeX/PDF: allow hyphenations in typewriter font.

  • User interface:

    • User interface is quite fancier, with progress bars and all

    • Debug/warning/info levels should be displayed in a more coherent manner

    • New --no-fancy option if you don’t like the fancy UI (or if it doesn’t work in your terminal)

    • New --force-emoji option to force emoji usage.

  • Library interface:

    • Removed Book::set_verbosity method (uses a logger library instead).

  • Now requires rustc >= 1.20.0

  • Breaking changes:

    • The template.tex template was quite modified. Crowbook now uses custom command for most markdown elements, defined in the template. This allow an user to redefine the way the book is rendered without having to modify Crowbook itself. Unfortunately, as tex templates for previous Crowbook versions won’t work anymore.

    • the resources.files option is now a YAML list of strings, instead of a comma-seprated string.

  • Add support for grammalecte grammar checker.

  • crowbook command takes a new argument, -S or --stats which displays stats on the book (currently, words and characters count).

  • Interactive fiction:

    • Added conditional blocks.

  • Options:

    • options can now take the “auto” value, which will infer the output file name based on the book file name.

    • output is a new option that can specify a series of format to render, with default output file name.

    • proofread.grammalecte and proofread.grammalecte.port allow respectively to enable grammar checking with Grammalecte and (optionnally) to specify the port to connect.

    • tex.margin.left, tex.margin.right, tex.margin.bottom and are new options that allow to specify margins for LaTeX/PDF outputs.

    • tex.paper_size was renamed tex.paper_size.

  • HTML:

    • Add JSON-LD structured data to the book’s HTML files.

  • Bugfixes:

    • LaTeX: fix rendering of part/chapter (part previously displayed as chapter and its first chapter as part)

    • EPUB:

      • Fix .rule so it is centered despite KOBO CSS injection.

    • Fix resources/images inclusion when they are symlinks to the actual file.

This release includes a few new features, such as the possiblity to include Markdown files as section/subsections and not only as chapter, experimental support for superscript and subscript, and yet more experimental support for writing interactive fiction.

  • Book configuration file:

    • It is now possible to include subchapters using the -- command (with one dash per sublevel: --- will include as a subsection).

  • Markdown:

    • Added support for superscript and subscript features, using respectively foo^up^ or bar~down~ syntax.

  • New options:

    • rendering.chapter: change what is displayed in place of “chapter”.

    • rendering.part: change what is displayed in place of “part”.

    • html.chapter.template and html.part.template allow to tune a little how the chapters and parts are displayed in HTML.

    • tex.hyperref, if set to false, will disable hyperrefs for local links. Can be useful for some files.

    • crowbook.html_as_text, if set to false, will not treat HTML as text but ignore it.

    • subtitle, as its name suggest, set the subtitle of a book.

    • crowbook.markdown.superscript can enable or disable superscript/subscript “extension”.

  • Rendering:

    • Change the way chapters are displayed by default.

    • PDF output now has a better-looking (hopefully) title page.

    • Internal links are a bit more flexible, e.g. if you link to Readme.html it will now try to link to the chapter corresponding to

  • Bugfixes:

    • LaTeX:

      • Fix bug in syntax highlighting.

      • Fix label placements (and thus navigation inside PDF document).

    • EPUB:

      • Add unnamed but numbered chapters to the TOC.

      • Fix HTML escaping issue for chapter titles.

      • Fix the way parts were handled in the TOC.

    • Book configuration file:

      • Fix issue when setting custom number for parts.

  • Crowbook now requires rustc >= 1.17.0

  • An image can now be considered standalone even if it is inside a link.

  • Bugfixes:

    • HTML/EPUB: use raw (not HTML rendered) metadata in the places where HTML code is not appropriate. Templates can use this metadata with the foo_raw value.

    • HTML/EPUB: fix double-escaping/rendering issues in titles.

    • EPUB:

      • Escape title and author before feeding them to epub-builder.

      • Fix content.opf issue by not rendering first chapter’s title (marked as beginning of document) in <guide>.

  • Rendering:

    • HTML/EPUB: standalone images are now displayed centered.

  • When crowbook parses the book’s contents, it now detects which features are used. This is useful in various ways:

    • The ODT renderer only displays a global warning showing the lists of used features that are not implemented, instead of a warning each time such a feature is encountered.

    • The LaTeX and HTML/EPUB renderers only initialize syntect (which can take some time) if code blocks are used in the document.

    • The LaTeX renderer only requires LaTeX packages that are actually used in the document.

  • Command-line interface:

    • Warnings are now displayed by default.

    • The (undocumented) --debug argument has been removed.

    • The status of some messages have been modified (“warning” to “debug” or “error” to “warning”).

  • Deprecated option:

    • crowbook.verbose has been deprecated, at it should be set by the CLI.

  • General:

    • When there is an error setting an option from the book configuration file (e.g. because it is an invalid key), print an error but do not abort, only ignore this specific option.

  • New options:

    • tex.stdpage: if set to true, will use the stdpage package to render the book according to standards for submitting manuscripts.

    • rendering.highlight.theme allows to specifies a theme for syntax highlighting (only used if rendering.highlight is set to “syntect”).

    • html.highlight.theme, epub.highlight.theme and tex.highlight.theme allow to specify a theme for HTML/EPUB/LaTeX renderers (only used with syntect).

  • Deprecated option:

    • proofread.nb_spaces.

  • Rendering:

    • [syntect]( is now the default for rendering.highlight. Concretely, this means that by default syntax highlighting is now done when crowbook is run instead of using [highlight.js](

    • EPUB:

      • Now sets the “cover-image” property and meta so readers should display cover correctly.

      • Narrow non-breaking spaces should display more correctly on KOBO ereaders (hoping this won’t break the way they are displayed everywhere else).

  • Proofreading:

    • Repetition detection is now a bit less of an hack, and should cause less problems when used in conjunction with grammar checking. It now also works on PDF output (so the way it is highlighted could be improved).

  • Bugfixes:

    • Fix mimetype of EPUB files (make sure it is always “stored” and not “deflated” by the zip command).

    • Avoid initializing syntect (at the cost of performances) if it is not used.

    • Avoid creating an empty file if some book renderer fails (e.g. EPUB or ODT because zip command is not present).

  • Rendering:

    • Avoid page break before or after a separating rule.

    • Add support for syntect for syntax highlighting. This is activated by setting rendering.highlight to syntect (see below).

    • EPUB:

      • Set back HTML escape of narrow non-breaking spaces to true by default (it caused problems on some readers, but cause much more serious one if false).

      • Add more information to guide/nav landmarks.

    • LaTeX/PDF:

      • Improve the way code blocks are displayed, using the mdframed package.

      • Try to reduce the issues of too long lines when using code and code blocks, by inserting \allowbreak{} directive after some characters (., /, _, ...).

      • Block quotes are now displayed in italics.

      • Tables now use tabularx, which allows to break too long lines (it still doesn’t break pages, though).

  • New options:

    • rendering.highlight can be set to none, highlight.js (by default, enables syntax highlighting via Javascript, but only on HTML document) or syntect (doesn’t necessitate javascript, and can work in EPUB or LaTeX, but more experimental at this point).

  • Deprecated options:

    • html.highlight_code (use rendering.highlight instead).

  • Bugfixes:

    • HTML (standalone): fix the template that contained invalid HTML code.

Substantial changes in this release, the more important one being support for parts!

  • Breaking changes: the API has undergone some breaking changes, hoping they will be the last ones for a while. API should now be more simple and consistent (?). This version contains also substantial options renaming (see below).

  • Crowbook now supports parts (above the “chapter” level), using the ‘@’ character in the book configuration file.

  • Command-line interface:

    • Behaviour of --to should now be consistent for all output formats.

    • If --output is set to -, prints to stdout.

    • Conversely, if <BOOK> is set to -, reads from stdin.

    • Path specified by --output is now interpreted relatively to current directory (and not depending on where <BOOK> is or its options).

  • Rendering:

    • Chapters with no titles now have an empty title added (so it can at least display e.g. “Chapter X”).

    • EPUB:

      • The toc.ncx file now displays links to “title” and (if set) “cover” (can be deactivated, see below).

      • The toc.ncx file now displays toc levels below chapter.

      • The table of contents is now displayed inline if rendering.inline_toc is set to true.

  • New options:

    • epub.toc.extras, set to true by default, will add links to the title and the cover (if it is set) in the table of contents.

    • epub.escape_nb_spaces, similar to html.escape_nb_spaces and set to false by default since at least Kobo reader don’t seem to be able to understand the CSS to escape those nb spaces...

    • rendering.chapter.roman_numerals, if set to true, will display chapter numbers using roman numerals.

    • rendering.part.roman_numerals, if set to true (it is by default) will display part numbers using roman numerals.

    • rendering.part.template specifies the numbering scheme of parts.

    • rendering.part.reset_counter, if set to true (it is by default), resets chapter number to zero after a part.

  • Renamed options:

    • import_config renamed to import.

    • rendering.chapter_template renamed to rendering.chapter.template.

    • html_single.html renamed to html.standalone.template.

    • html_single.js renamed to html.standalone.js.

    • html_single.one_chapter renamed to html.standalone.one_chapter.

    • output.html_dir renamed to output.html.dir.

    • output.proofread.html_dir renamed to output.proofread.html.dir.

    • html_dir.index.html and html.dir.chapter.html have been merged and both renamed to html.dir.template.

    • tex.font_size renamed to tex.font.size.

  • Bugfixes:

    • EPUB:

      • Fix duplicate HTML escaping (resulting in e.g. “&” instead of “&”).

    • HTML directory:

      • Fix panic when trying to generate html directory in “../xxx” (#23).

      • Fix “previous chapter” links that were not displayed when “html.header” was set.

    • HTML:

      • Fix the way initial letter is displayed if rendering.initials is true.

  • Internationalization:

    • Strings in generated Crowbook documents (such as “Table of contents”, “Title”, “Cover” and such) are now translated in spanish.

  • New options:

    • tex.font_size specifies an optional font size (in pt) passed to the LaTeX class (must be 10, 11 or 12).

    • tex.title can be set to false to avoid rendering the title with \maketitle.

    • tex.paper_size specifies the paper size for PDF output.

    • tex.template.add, html.css.add and epub.css.addallow to specify inline LaTex or CSS code in the book configuration file that will be added respectively to tex.template.add, html.css.add and epub.css.add.

    • html.icon allows to specify the path of an icon for HTML documents.

  • Command-line interface:

    • Paths that are displayed should now be normalized, e.g. “foo/bar.pdf” instead of “baz/../foo/bar.pdf”.

  • Rendering:

    • HTML:

      • The default CSS style has been slightly modified.

  • Building:

    • Crowbook now requires rustc >= 1.13.0 to build.

    • Pre-built binaries now all include the proofreading feature.

    • Linux binaries are now linked against musl library so they should really work on any Linux platform.

  • Bugfixes:

    • Fixed escaping of author and title fields.

    • Fixed text cleaning in ODT rendering that causes corrupt files to be generated.

  • CommandLine Interface:

    • Crowbook displays clearer error messages when unable to launch latex or zip commands.

    • Crowbook uses term library in order to display colors correctly on e.g. Windows.

    • The new argument --lang (or -L) allows to set the runtime language used by Crowbook, overriding LANG environment variable.

    • --list-options no longer uses colors as it caused problems depending on the terminal or when piping to less.

Only minor changes in this version:

  • Options:

    • author and title’s default values are both set to the empty string, instead of Anonymous and Untitled.

    • input.autoclean has been renamed input.clean.

    • input.smart_quotes has been renamed input.clean.smart_quotes.

    • new option: input.clean.ligature.dashes will (if set to true) replace -- to en dash () and --- to em dash ().

    • new option: input.clean.ligature.guillemets will (if set to true) replace << and >> to french guillemets (« and »).

  • Rendering:

    • HTML: if html_single.one_chapter and rendering.inline_toc are both set to true, only render the TOC if currently displayed chapter is the first.

Fixed a bug in fr.po translation that prevented building from fresh install.

This release contains some breaking changes (mostly for the API, which has been split in separate libraries). It alse features some internationalization support, and the program should now be tranlated if your LANG environment variable is set to french.

  • Breaking changes:

    • Templates:

      • Conditional inclusion depending on lang must now be done using lang_LANG (e.g. lang_fr, lang_en, and so on). This might impact custom epub.css and html.css templates.

    • API:

      • The escape module has been moved to a separate crate, crowbook_text_processing. The cleaner module is no longer public, but the features it provided are also available in crowbook_text_processing.

  • New options:

    • html.css.colors allows to provide a CSS file that only redefine the colour scheme. Such a file can be built from crowbook --print-template html.css.colors.

    • input.smart_quotes: if set to true, tries to replace ' and " by curly quotes.

  • Command line interface:

    • Crowbook is now (imperfectly) localized in french, and can be translated to other languages.

    • Added the --quiet (or -q) argument, that makes crowbook run without displaying any messages (except some error messages at this point).

  • Rendering:

    • HTML:

      • The table of contents menu is no longer displayed in the HTML single renderer if it doesn’t contain at least two elements.

      • The default colour theme has been modified a little.

  • Bugfixes:

    • Fix the escaping of non-breaking spaces in EPUB, as &nbsp; and its friends aren’t valid entities in XHTML, apparently.

This release mainly introduces generation of proofreading copies, allowing, if they are set (and crowbook was compiled with the proofread feature) to generate proofreading copies, using tools to check grammar and detect repetitions. These features are currently experimental.

  • New options:

    • html.escape_nb_spaces, if set to true (by default), will replace unicode non breaking spaces with HTML entites and CSS so it can display correctly even if reader’s don’t have a browser/font supporting these unicode symbols.

    • Output files for proofread documents: output.proofread.html, output.proofread.html_dir and output.proofread.pdf.

    • Proofread options proofread.repetitions and proofread.nb_spaces have been added.

      • proofread.nb_spaces, if set to true, highlights non-breaking spaces so it is easier to check the correct typography of a book. Note that it requires that html.escape_nb_spaces be set to true (default) to work.

      • proofread.reppetitions, if set to true, uses Caribon to highlight repetitions in a document. It also uses the settings proofread.repetitions.fuzzy, proofread.repetitions.max_distance, proofread.repetitions.threshold, proofread.repetitions.fuzzy.threshold, proofread.repetitions.ignore_proper. Note that this feature is not built by default, you’ll have to build crowbook with cargo build --release --features "repetitions".

  • New default settings for options:

    • tex.command is now xelatex by default.

  • Rendering:

    • LaTeX:

      • Add support for xelatex in the default template.

    • Improved french cleaner (see an article (in french) that talks about what it does).

  • Crowbook user guide: documentation has been updated to correctly reflect 0.9.x options.

  • API:

    • clap dependency is now optional, people who want to use Crowbook as a library should include it with crowbook = { version = "0.9", default-features = false }. (clap is still required to build a working binary).

The main objective of this release is to clean public interfaces, in order to limit breaking changes in the future. Ideally, all pre-1.0 releases should thus be 0.9.x. Concretely, this meant three things:

  • reducing the surface of Crowbook’s library API;

  • cleaning options names

  • cleaning the names exported in templates and document them, in order not to break user-defined templates in future (non-breaking) releases. More detailed changes for this release:

  • Breaking change for users: removed tex.short option, replaced by a more generic tex.class (default being book). html.crowbook_link has also been removed.

  • Renamed options. Using the old name will print a deprecation warning but will still work for a while.

    • temp_dir -> crowbook.temp_dir

    • zip.command ->

    • verbose -> crowbook.verbose

    • html.print_css -> html.css.print

    • html.display_chapter -> html_single.one_chapter

    • html.script -> html_single.js

    • numbering -> rendering.num_depth

    • numbering_template -> rendering.chapter_template

    • display_toc -> rendering.inline_toc

    • toc_name ->

    • enable_yaml_blocks -> input.yaml_blocks

    • use_initials -> rendering.initials

    • autoclean -> input.autoclean

    • html_dir.css -> html.css (not really renamed, html_dir.css isactually removed as there is no point in having different CSS for standalone and multifile HTML rendering, is it?)

  • New options:

    • More metadata: license, version and date. These metadata are not treated by the renderers, but they are exported to the templates: {{{metadata}}} allows to access the content. If they are present, a has_metadata is also set to true, allowing to do something like {{{title}}} {{#has_version}}version {{{version}}} {{/has_version}}.

    • Yet more metadata: it is possible to add custom metadata by prefixing it with metadata.. They will then be accessible in the templates, with dots ('.') replaced by underscores ('_'). E.g., with bar you can access it in your templates with {{{metadata_foo}}}.

    • output.base_path specifies a directory where the output files (set by output.FORMAT will be written.

    • resources.base_path.templates specifies where templates can be found.

  • Rendering:

    • Metadata can now contain Markdown and will be rendered by the renderers. This might not be a good idea for common fields (e.g. “title”), though. Use with caution.

    • can use {{{loc_toc}}} to specify a localized name.

    • HTML:

      • and hstml.footer are now considered as templates, so you can use some {{{metadata}}} in it.

      • Improved the way footnotes are displayed.

      • In standalone HTML, footnotes are rendered at the end of the document instead of at the end of the chapter, unless html_single.one_chapter is true.

    • LaTeX:

      • If tex.class is set to article, chapters will be displayed as \sections since article class doesn’t handle chapters.

      • Except if tex.class is set to book, margins are now symmetrical.

      • LaTex template now uses version and date.

  • Bugfixes:

    • import_config only import options from another book file that are not equal to the default ones and that haven’t already been set by the caller. E.g., author: foo then import_config: won’t erase the author previously set.

    • import_config now correctly translates the imported book’s paths.

  • Crowbook program:

    • Still working to improve error messages.

    • crowbook --list-options uses colors. This might hurt your eyes.

    • Display an error message when mustache can’t compile a template, instead of panicking.

  • Internal/API:

    • Added static methods to Logger to allows displaying messages more easily/prettily.

    • Reduce pubic API’s surface so less changes will need to be considered breaking in the future.

This release adds support for syntax higlighting in code blocks, customized top and footer blocks for HTML rendering, and the special import_config option that allows to import options from another book file. It also provides (hopefully) better error messages.

  • New options:

    • import_configis not really an option, but allows to import another configuration file, useful if you share a same set of options between multiple books.

    • use_initials (set to false by default) makes Crowbook use initials (“lettrines”) at start of each chapter. Support is still experimental.

    • html.highlight_code (set to true by default) allows syntax highlighting for code blocks, using highlight.js.

    • html.higlight.css and html.highlight.js can be used to provide other themes (default is default.css) and an highlight.js build that support other languages.

    • html.footer allows to specify custom footer. If not set, html.crowbook_link allows to disable “Generated by Crowbook” message.

    • allows to specify a custom header that will be displayed at the top of HTML file(s).

  • Deprecated options:

    • side_notes has been renamed html.side_notes.

  • Crowbook program:

    • All output formats are now rendered concurrently.

    • Better error messages. Crowbook now tries to give more information when displaying an error, with the file name where a problem was found, and, in some cases, the line. It also tries to detect errors (such as files not found) sooner.

    • Some “warning” messages have also been “moved” to error messages, to make sure they are displayed even when crowbook isn’t runned with --verbose.

  • Rendering:

    • Hidden chapter now produce empty \chapter*{} and <h1> in LaTeX and HTML. This allow to delimit a chapter break even if nothing is displayed.

  • Bugfixes:

    • Navigation menu of standalone HTML didn’t include a call to javascript when html.display_chapter was set to true, meaning it didn’t display the chapter correctly.

    • Implementations of Image and StandaloneImage were reversed in LaTeX.

    • StandaloneImage urls were not adjusted (meanning that running crowbook from another directory failed).

    • Image paths are now found correctly in HtmlDir rendering even if crowbook is called from another directory (same fix as 0.6’s for Epub and LaTeX, which was forgotten for HtmlDir).

  • Internal/API:

    • In order to have better error messages, there was a need to refactor the Error type, and make more methods return Result<X> instead of X. The API is, therefore, quite modified.

    • Added a Renderer trait used by the various renderers.

    • Removed some methods from public API.

This releases renders images differently when they are on a standalone paragraph or inside a paragraph.

  • Internal/API:

    • Token has a new variant, StandaloneImage. This is used to distinguish an image that is alone in a paragraph of an image that is inlined alongside text.

    • Parser.parse method now distingues between Image and StandaloneImage. Currently, an image is considered “standalone” if it is the sole element of a paragraph, even if it is among a link.

    • Token has a new is_image method.

  • Rendering:

    • Standalone images are now rendered differently than inline images (80% of width VS original size) in HTML/EPUB and LaTeX.

  • Deprecated options:

    • nb_char: since it was only used for french cleaner and for typography reasons it’s better to use different non breaking spaces according to context, this option was not really useful anymore.

  • Rendering:

    • Images are now displayed at 80% width of the page.

  • Bugfixes:

    • Image paths are now found correctly in LaTeX and EPUB rendering even if crowbook is called from another directory.

    • Fixed a bug in French cleaner when a string to clean ended by a non-breaking space (space was doubled with a breaking one).

    • LaTeX/PDF:

      • “Autocleaning” is now also activated (for french at least) for LaTeX rendering, since it doesn’t correctly insert non-breaking spaces for e.g. ‘«’ or ‘»’.

      • Fixed escaping of -- to -{}- to avoid tex ligatures.

    • HTML/EPUB:

      • html.display_chapter now defaults to false (e.g., by default the HTML displays the entirety of a book).

      • Fixed rendering of lists when lang is set to fr.

      • Links are now HTML-escaped, fixing errors in XHTML (for EPUB rendering) when links contained ‘&’ character.

Mostly rendering fixes:

  • Epub:

    • Fix a validation problem when book contained hidden chapters.

  • French cleaner:

  • HTML:

    • Add viewport meta tags.

    • Standalone HTML:

      • Don’t display the button to display chapter and the previous/next chapter link if html.display_chapter is set to false.

      • Fix chapter displaying when some chapters are not numbered.

    • Multi-files HTML:

      • Fix previous/next chapter display to make it consistent with standalone HTML.

  • Crowbook now requires Rustc 1.7.0.

  • It is now possible to render HTML in multiple files:

    • output.html_dir will activate this renderer, and specify in which directory to render these files;

    • html_dir.css allows to override the CSS for this rendering;

    • html_dir.index.html allows to specify a template for the index.html page;

    • html_dir.chapter.html allows to specify a template for the chapters pages.

  • New book options:

    • tex.short: if set to true, the LaTeX renderer will use article instead of book as document class, and will use the default \maketitle command for article. This option is by default set to false, except when Crowbook is called with --single.

    • enable_yaml_blocks: parsing YAML blocks is no longer activated by default, except when using --single. This is because you might want to have e.g. multiple short stories using YAML blocks to set their titles and so on, and a separate .book file to render a book as a collection of short stories. In this case, you wouldn’t want the displayed title or the output.pdf/html/epub files be redefined by the short stories .md files.

    • html.print_css: allows to specify a stylesheet for media print

    • html.display_chapter: displays one chapter at a time in standalone HTML

    • html.script: allows to specify a custom javascript file for standalone HTML

    • html_dir.script: same thing for multipage HTML

    • resources.base_path: by default, Crowbook resolves local links in markdown files relatively to the markdown file. This option allows to resolve them relatively to a base path. This option comes with two variants, resources.base_path.images and resources.base_path.links, which only activate it for respectively images tags and links tags. These two options are ignored when base_path is set. There is also resources.base_path.files which specify where additional files (see below) should be read, but this is one is set to . (i.e., the directory where the .book file is) by default.

    • resources.files: indicate a (whitespace-separated) list of files that should be embedded. Currently only used with the EPUB renderer.

    • resources.out_path: indicate where resources.files should be copied in the final document. Default to data, meaning that files will be placed in a data directory in the EPUB.

  • Rendering:

    • Templates can now use localized strings according to the lang option

    • Standalone HTML now includes locale files using base64.

    • Standalone HTML displays one chapter at a time, thouht it can be changed via a button in the menu.

    • HTML/EPUB: default CSS now uses the lang value do determine how to display lists (currently the only difference is it uses “–” when lang is set to “fr” and standard bullets for other languages).

  • Bugfixes:

    • Fixed a bug of filename “resolution” when Crowbook was called with --single (e.g., crowbook -s tests/ would previously try to load tests/tests/

    • Epub renderer now uses the mime_guess library to guess the mime type based on extension, which should fix the mime type guessed for a wide range of extensions (e.g., svg).

  • Internal/API:

    • The Book::new, new_from_file, and new_from_markdown_file take an additional options parameter. To create a book with default options, set it to &[].

  • Crowbook now internally uses a true YAML parser, yaml_rust, for its options. Since the “old” Crowbooks’s config format was similar, but had some subtle differences, this is somewhat of a breaking change:

    • strings should now be escaped with “” in some cases (e.g. if it contains special characters). On the other hand, it allows to optionally escape a string with these quotes, which wasn’t possible until then and might be useful in some cases.

    • multiline strings now follow the YAML format, instead of the previous “YAML-ish” format. This can impact the way newlines are added at the end of a multiline string. See e.g. this link for the various ways to include mulitiline strings in Yaml.

  • Crowbook now parses YAML blocks (delimited by two lines with “---”) in Markdown files, ignoring keys that it doesn’t recognize. This allows crowbook to be compatible(-ish) with Markdown that contains YAML blocks for Jekyll or Pandoc.

  • New option --single allows to give Crowbook a single Markdown file (which can contain options within an inline YAML block) instead of a book configuration file. This is useful for e.g. short stories.

  • Enhanced the way debugging/warning/info messages are handled and displayed:

    • Added a --debug option to the binary.

    • Internal: added a Logger struct.

    • Different levels of information (debug/warning/info/error) get different colors.

  • Bugfixes:

    • Crowbook no longer crashes when called with the --to argument if it can’t create a file.

  • Crowbook now tries to convert local links. That is, if you link to a Markdown file that is used in the book. (e.g., it should link to an appropriate inner reference inside the book.

  • Latex renderer now supports (local) images.

  • Epub renderer now embed (local) images in the EPUB file.

  • Some changes to the HTML/Epub stylesheets.

  • Internal (or usage as a library):

    • Crowbook no longer changes current directory, which worked in the binary but could cause problem if library was used in multithreaded environment (e.g. in cargo test).

    • More modules and methods are now private.

    • Improved documentation.

    • Added more unit tests.

  • Bugfixes:

    • Epub renderer now correctly renders unnumbered chapter without a number in its toc.ncx file

  • Bugfixes:

    • French cleaner now correctly replaces space after — (in e.g. dialogs) with “em space”.

  • Bugfixes:

    • HTML/Epub rendering no longer incorrectly increment chapter count for unnumbered chapters.

    • Latex: makes what is possible to avoid orverflowing the page.

  • Minor changes:

    • Latex: improvement of the default way URLs are displayed.

  • Command line arguments:

    • New argument --print-template now allows to print a built-in template to stdout.

    • New argument --list-options prints out all valid options in a config file (or in set), their type and default value.

    • New argument --set allows to define or override whatever option set in a book configuration.

    • --create can now be used without specifying a BOOK, printing its result on stdout.

  • Configuration file:

    • Added support for multiline strings in .book files, with either ‘|’ (preserving line returns) or ‘>’ (transforming line returns in spaces)

    • New option display_toc allows to display the table of contents (whose name, at least for HTML, is specified by toc_name) in HTML and PDF documents.

    • Option numbering now takes an int instead of a boolean, allowing to specify the maximum level to number (e.g. 1: chapters only, 2: chapters and sectino, ..., 6: everything).

  • Rendering:

    • Added support for numbering all headers, not just level-1 (e.g., having a subsection numbered 2.3.1).

    • Tables and Footnotes are now implemented for HTML/Epub and LaTeX output.

  • Internal:

    • Refactored Book to use an HashMap of BookOptions instead of having like 42 fields.

  • initial release


                   Version 2.1, February 1999

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