Parle pattern matching

Table of Contents

Parle supports regex matching similar to flex. Also supported are the following POSIX character sets:

  • [:alnum:]
  • [:alpha:]
  • [:blank:]
  • [:cntrl:]
  • [:digit:]
  • [:graph:]
  • [:lower:]
  • [:print:]
  • [:punct:]
  • [:space:]
  • [:upper:]
  • [:xdigit:]
.

The Unicode character classes are currently not enabled by default, pass --enable-parle-utf32 to make them available. A particular encoding can be mapped with a correctly constructed regex. For example, to match the EURO symbol encoded in UTF-8, the regular expression [\xe2][\x82][\xac] can be used. The pattern for an UTF-8 encoded string could be [ -\x7f]{+}[\x80-\xbf]{+}[\xc2-\xdf]{+}[\xe0-\xef]{+}[\xf0-\xff]+.