hachoir-regex Manipulation of regular expressions (regex) Hachoir regex ============= hachoir-regex is a Python library for regular expression (regex or regexp) manupulation. You can use a|b (or) and a+b (and) operators. Expressions are optimized during the construction: merge ranges, simplify repetitions, etc. It also contains a class for pattern matching allowing to search multiple strings and regex at the same time. Website: http://bitbucket.org/haypo/hachoir/wiki/hachoir-regex Changelog ========= Version 1.0.3 * Raise SyntaxError on unsupported escape character * Two dot atoms are always equals Version 1.0.2 (2007-07-12) * Refix PatternMatching without any pattern Version 1.0.1 (2007-06-28) * Fix PatternMatching without any pattern Version 1.0 (2007-06-28) * First public version Regex examples ============== Regex are optimized during their creation: >>> from hachoir_regex import parse, createRange, createString >>> createString("bike") + createString("motor") <RegexString 'bikemotor'> >>> parse('(foo|fooo|foot|football)') <RegexAnd 'foo(|[ot]|tball)'> Create character range: >>> regex = createString("1") | createString("3") >>> regex <RegexRange '[13]'> >>> regex |= createRange("2", "4") >>> regex <RegexRange '[1-4]'> As you can see, you can use classic "a|b" (or) and "a+b" (and) Python operators. Example of regular expressions using repetition: >>> parse("(a{2,}){3,4}") <RegexRepeat 'a{6,}'> >>> parse("(a*|b)*") <RegexRepeat '[ab]*'> >>> parse("(a*|b|){4,5}") <RegexRepeat '(a+|b){0,5}'> Compute minimum/maximum matched pattern: >>> r=parse('(cat|horse)') >>> r.minLength(), r.maxLength() (3, 5) >>> r=parse('(a{2,}|b+)') >>> r.minLength(), r.maxLength() (1, None) Pattern maching =============== Use PatternMaching if you would like to find many strings or regex in a string. Use addString() and addRegex() to add your patterns. >>> from hachoir_regex import PatternMatching >>> p = PatternMatching() >>> p.addString("a") >>> p.addString("b") >>> p.addRegex("[cd]") And then use search() to find all patterns: >>> for start, end, item in p.search("a b c d"): ... print "%s..%s: %s" % (start, end, item) ... 0..1: a 2..3: b 4..5: [cd] 6..7: [cd] You can also attach an objet to a pattern with 'user' (user data) argument: >>> p = PatternMatching() >>> p.addString("un", 1) >>> p.addString("deux", 2) >>> for start, end, item in p.search("un deux"): ... print "%r at %s: user=%r" % (item, start, item.user) ... <StringPattern 'un'> at 0: user=1 <StringPattern 'deux'> at 3: user=2 Installation ============ With distutils: sudo ./setup.py install Or using setuptools: sudo ./setup.py --setuptools install http://bitbucket.org/haypo/hachoir/wiki/hachoir-regex Victor Stinner 1.0.3