use upquote.sty if exists (http://mathematicalcoffee.blogspot.com/201…

…2/03/getting-straight-single-quotes-for.html)
yihui · Apr 14, 2012 · b4934de · b4934de
1 parent 960e573
commit b4934de
Showing 1 changed file with 2 additions and 1 deletion.
diff --git a/R/header.R b/R/header.R
@@ -97,7 +97,8 @@ set_header = function(...) {
 
 .default.sty = file.path(.inst.dir, 'themes', 'default.css')
 # header for Latex Syntax Highlighting
-.header.hi.tex = paste(theme_to_header_latex(.default.sty)$highlight,
+.header.hi.tex = paste(c('\\IfFileExists{upquote.sty}{\\usepackage{upquote}}{}',
+                         theme_to_header_latex(.default.sty)$highlight),
                        collapse = '\n')
 .header.framed = paste(readLines(file.path(.inst.dir, 'misc', 'knitr.sty')),
                        collapse = "\n")