Added a new engine md to output Markdown text both
verbatim and as-is, which can be useful for showing Markdown examples,
e.g.,
```{md}
You can see both the _source_ and _output_ of
this `md` chunk.
```
You can also use `{md} the engine **inline**`.Added a new engine mermaid to generate Mermaid
diagrams, e.g.,
```{mermaid, fig.cap='A nice flowchart.'}
graph TD;
A-->B;
A-->C;
B-->D;
C-->D;
```Added helper functions pkg_desc(),
pkg_news(), pkg_citation(),
pkg_code(), and pkg_manual() to get various
package information for building the full package documentation as a
single-file book (thanks, @jangorecki @llrs #24, @TimTaylor #22).
LaTeX math environments such as equations can be numbered and cross-referenced now (thanks, @hturner, #32).
Section headings containing the class name “unlisted” will be excluded in the table of contents.
Provided a way to write <span> with attributes
based on empty links, i.e., [text](){.class #id ...}. The
empty URL here tells mark() to treat the link as a
<span> instead of <a>.
Added back/forward/refresh/print buttons to the toolbar in the
litedown::roam() preview interface.
Changed the behavior of .Rmd and .R
file links in the litedown::roam() interface: previously,
clicking on an .Rmd or .R filename will
execute them; now it will only show their content, because fully
executing the code may be expensive or even dangerous (especially when
the files were not authored by you). A new “Run” button has been
provided in the interface, on which you can click on to run a file in
memory and preview it (i.e., the old behavior of clicking on filenames).
You should use this button only if you trust the file.
Added the JS asset @mathjax-config
to enable equation numbering by default when the JS math library is set
to MathJax (thanks, @hturner, #32).
Set options(bitmapType = 'cairo') in
fuse() if capabilities('cairo') is TRUE, which
will generate smaller bitmap plot files (e.g., .png) than
using quartz or Xlib, and is also a safer
option for fuse() to be executed in parallel
(rstudio/rmarkdown#2561).
Added a new vignette engine litedown::book to make
it possible to build multiple vignettes into a book. To use this engine,
declare \VignetteEngine{litedown::book} only in the book
index file (e.g., index.Rmd) but not in other book chapter
files.
Added support for an array of multiple authors in the YAML
metadata (thanks, @AlbertLei, #28). If the
author field in YAML is an array of length > 1, each
author will be written to a separate <h2> in HTML
output, or concatenated by \and in LaTeX output. Note that
you can also write multiple authors in a single string (e.g.,
author: "Jane X and John Y") instead of using an array
(author: ["Jane X", "John Y"]), in which case the string
will be treated as a single author (they will be put inside a single
<h2> in HTML output).
Fixed the bug that the leading -, +, or
* in a LaTeX math expression was recognized as the bullet
list marker, which would invalidate the math expression (thanks, @hturner, #33).
Changed the first - to : in
automatically generated element IDs, including section, figure, and
table IDs, e.g., the ID sec-intro-methods is changed to
sec:intro-methods, and fig-nice-plot is
changed to fig:nice-plot. You can still use -
when manually assigning IDs to elements, e.g.,
# Intro Methods {#sec-intro-methods}. For backward
compatibility, cross-references using - will be resolved if
the : version of the ID can be found, e.g.,
@sec-intro-methods will be resolved to
@sec:intro-methods if the former cannot be found but the
latter can.
Fixed a bug that when LaTeX math environments are written in raw
LaTeX blocks (i.e., ```{=latex}), mark() will
not load the math JS library such as MathJax or KaTeX unless
$ $ or $$ $$ expressions are present in the
document.
As-is output accepts attributes via the chunk option
attr.asis now. If provided, as-is output will be wrapped in
a fenced Div with these attributes.
Numeric output from inline code will no longer be formatted if
the value is wrapped in I().
The prefix for the automatic IDs of h1 headings has
been changed from sec: to chp:. For other
levels of headings, the prefix is still sec:.
Provided a new option embed_cleanup to clean up plot
files that have been embedded in HTML output (thanks, @TimTaylor,
#16).
fuse() supports the output format
litedown::markdown_format now, which generates the
intermediate Markdown from R Markdown without further rendering Markdown
to other formats. Using this output format is equivalent to
fuse(..., output = '.md') or
fuse(..., output = 'markdown') (thanks, @mikmart, #35).
A data frame (or matrix/tibble) wrapped in I() is
fully printed to a table now by default. Without I(), data
objects are truncated to 10 rows by default when printing to
tables.
When options(litedown.fig.alt = TRUE) and the chunk
option fig.alt is unset, fuse() will emit
reminders about the missing alt text for code chunks containing plots
(thanks, @TimTaylor, #23). Providing alt text can
improve the accessibility of images in HTML output. To avoid omitting
the alt text inadvertently, you can set the option
litedown.fig.alt in your .Rprofile.
Added the meta variable plain-title for HTML output,
which is the plain version of the document title (i.e., without HTML
tags), and used in the <title> tag.
Check boxes from - [ ] ... are no longer disabled in
HTML output.
The implicit latest version of jsdelivr resources will be
resolved to an explicit version, e.g.,
https://cdn.jsdelivr.net/npm/@xiee/utils/css/default.css
will be resolved to
https://cdn.jsdelivr.net/npm/@xiee/utils@X.Y.Z/css/default.css,
where X.Y.Z is the current latest version. This will make
sure the HTML output containing jsdelivr resources is stable.