(⬑Main Module Docs)
JavaScript-style Regular Expressions
- Source code: /dir/s2/mod/regex_js?ci=trunk
- Test/demo code:
ACHTUNG (2020-03-01): since this plugin was written, numerous regex bugs have been discovered in the upstream JS-regex library upon which it is based. In short, its results currently cannot be trusted:
https://github.com/ccxvii/mujs/issues/130
This library has two distinct regular expression modules with nearly-identical APIs: the common features are described in the POSIX regex module docs and this page describes only those features peculiar to this flavor.
This module, ported in from Tor Andersson's MuJS project, provides support for JavaScript-style regular expressions, noting that only the pattern syntax is JS-like, not the API of the compiled RegExp objects. e.g. these cannot (unlike in JS) be used to iterate over a string looking for multiple matches. (That said, the first time i desperately want/need such a feature, something approximating it will be added!)
JS-flavor Compilation Flags
See also: POSIX compilation flags
Regex compilation may be modified by providing a string of single-letter flags. Unknown flags cause an exception to be thrown. The flags for this module are listed below. The upper-case names listed next to each flag are the C-level names for the flags.
"i"(ICASE): make the regex case-insensitive."n"(NEWLINE): tells the$end-of-pattern anchor (e.g.foo$) to also match at the end of a line (i.e. at anewline character). e.g. with this flag, the input textfoo\nbarwould match the patternfoo$, but it would not match without this flag.
JS-flavor Match-time Flags
See also: POSIX match-time flags
Like compilation flags, flags which change regex matching behaviour at match-time may be provided as a string of letters describing the flag(s):
"b"(NOTBOL): do not treat the beginning of the input string as thebeginning of a line. That is, do not match^Xat the start of the input.