Release knitr 1.42 · yihui/knitr

NEW FEATURES

Better .qmd (Quarto) file support:
- purl() will keep the in-chunk YAML syntax for options in the tangled R file
- knit() will produce a .md file instead of .txt
Users can specify a custom progress bar for knit() now. The default is still a text progress bar created from utils::txtProgressBar(). To specify a custom progress bar, set options(knitr.progress.fun = function(total, labels) {}). This function should take arguments total (the total number of chunks) and labels (the vector of chunk labels), create a progress bar, and return a list of two methods: list(update = function(i) {}, done = function() {}). The update() method takes i (index of the current chunk) as the input and updates the progress bar. The done() method closes the progress bar. See https://yihui.org/knitr/options/#global-r-options for documentation and examples.
The default text progress bar is still written to stdout() by default, but can also be written to other connections or stderr() now. To do so, set options(knitr.progress.output = ) to a connection or stderr().
Allow concordances to be embedded in HTML output (thanks, @dmurdoch, #2200).

knit() no longer prints out chunk options beneath the text progress bar while knitting a document (thanks, @hadley, #1880).
Due to a change in the evaluate package, the chunk options message = FALSE and warning = FALSE will completely suppress the messages/warnings now, instead of sending them to the console. To get back to the old behavior, you can use NA instead of FALSE (thanks, @gadenbuie, yihui/yihui.org#1458).
The stringr dependency has been removed. All string operations are done with base R now (thanks, @HughParsonage #1549 #1552, @rich-iannone #2174 #2177 #2186 #2187 #2195 #2202 #2205).

Improved the error message when inline R code cannot be parsed (thanks, @hadley #2173, @rich-iannone #2198).
If the chunk option child is used for a code chunk but the chunk is not empty, you will get a warning indicating that this non-empty code will not be executed when you knit the document. Now this warning can be silenced by options(knitr.child.warning = FALSE) (thanks, @jwijffels, #2191).
Devices from the package cairoDevice (Cairo_pdf, Cairo_png, Cairo_ps, Cairo_svg) are no longer supported since the package has been archived on CRAN for more than a year (thanks, @jessekps, #2204).

The sql engine now correctly prints tables with NA in the first column (thanks, @mariusbommert, #2207).