Log Message:
(print/R-knitr) Updated 1.48 to 1.49

(w3m -insecure -dump -T text https://github.com/yihui/knitr/releases)
knitr 1.49 Latest

NEW FEATURES

  * In-chunk references of the form <<label>> can be disabled via \ 
the chunk
    option ref.chunk = FALSE now (thanks, @jennybc @gadenbuie, #2360).

  * Added support for fig.alt for LaTeX output, i.e., using \includegraphics
    [alt={alt text}] (thanks, @capnrefsmmat, #2378).

  * The environment in which code chunks are evaluated can be changed by
    passing a custom environment to knit_global() now (thanks, @abhsarma, #2358
    ).

BUG FIXES

  * In-chunk references of the form <<label>> should not be resolved \ 
if label
    is not found in the document (thanks, @jennybc @gadenbuie, #2360).

  * The chunk option autodep = TRUE stopped working due to a regression from #
    2321 (thanks, @heavywatal #2344, @atusy #2377).

  * asis_output() was not passed to the output hook (thanks, @cderv, #2332).

  * Avoid partial matching of the Date/Publication field when generating
    citation('knitr'), otherwise R will emit a warning when options
    (warnPartialMatchDollar = TRUE) (thanks, @fkohrt, #2361).

MAJOR CHANGES

  * Unbalanced chunk delimiters (fences) in R Markdown documents are strictly
    prohibited now.

  * For code chunks with error = TRUE, purl() and hook_purl() will wrap the
    code in try({...}) (thanks, @bastistician #2338, @jeroen #2368).

MINOR CHANGES

  * If a character value is passed to the chunk option message or warning, it
    will be coerced by as.logical(), e.g., a character string "NA" will be
    coerced to NA (thanks, @cderv, #2375).

  * Issue a warning when the chunk option dependson receives an invalid value
    (thanks, @otoomet, #2376).

  * Changed the format of the reference card from PDF to HTML so building this
    package will not require LaTeX. See vignette('knitr-refcard', package =
    'knitr').

  * Switched the vignette engine from knitr to litedown::vignette for some
    package vignettes.