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Re: Limited regex support in newlib cripples syntax highlighting in nano


Reini Urban wrote:
2008/8/1 Tomi Belan wrote as "Limited regex support in newlib cripples
syntax highlighting in nano"
Cygwin regex.h implementation doesn't support some special sequences,
for example \< (beginning of word), \> (end of word) and \b (word
boundary). This causes a usability bug with the nano editor, which
uses these sequences extensively in most of its syntax highlighting
rules.

Posix regex is much faster then perl-style pcre regex. Syntax highlighter usually prefer fast over complete. So the term "crippled" should be used with care.

See e.g. http://swtch.com/~rsc/regexp/regexp1.html - Regular
Expression Matching Can Be Simple And Fast (but is slow in Java, Perl,
PHP, Python, Ruby, ...)  - which complains about the typical POSIX
spencer implementation also.

Interesting paper!


Judging from the linked efficient implementations, it could be interesting to have TRE library <http://laurikari.net/tre/> in Cygwin.

But judging from our own "man regexp" it should already have back-references (??):
"Regexec is largely insensitive to RE complexity except that back references are massively expensive."




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