closes yihui#110 by adding a new component in patterns: inline.comment

inline comments will be stripped off; this only happens to LaTeX currently

R/parser.R

@@ -153,6 +153,10 @@ print.block = function(x, ...) {
 
 ## extract inline R code fragments (as well as global options)
 parse_inline = function(input) {
+  inline.comment = knit_patterns$get('inline.comment')
+  if (!is.null(inline.comment)) {
+    input = str_replace(input, inline.comment, '') # strip off inline comments
+  }
   input = str_c(input, collapse = '\n') # merge into one line
 
   locate_inline = function(input, pattern) {

R/pattern.R

@@ -10,6 +10,7 @@ all_patterns = list(
   `rnw` = list(chunk.begin = '^<<(.*)>>=', chunk.end = '^@\\s*%*',
                inline.code = '\\\\Sexpr\\{([^}]*)\\}',
                input.doc = '(^|\n) *\\\\SweaveInput\\{([^}]*)\\}',
+               inline.comment = '^\\s*%.*',
                ref.chunk = '^\\s*<<(.*)>>\\s*$',
                global.options = '\\\\SweaveOpts\\{([^}]*)\\}',
                header.begin = '\n*\\s*\\\\documentclass[^}]+\\}',
@@ -21,6 +22,7 @@ all_patterns = list(
   `tex` = list(chunk.begin = '^%+\\s*begin.rcode\\s*(.*)',
                chunk.end = '^%+\\s*end.rcode', chunk.code = '^%+',
                ref.chunk = '^%+\\s*<<(.*)>>\\s*$',
+               inline.comment = '^\\s*%.*',
                global.options = '%+\\s*roptions\\s*([^\n]*)',
                inline.code = '\\\\rinline\\{([^}]*)\\}',
                header.begin = '\n*\\s*\\\\documentclass[^}]+\\}',