.. module:: ure
   :synopsis: regular expressions

This module implements regular expression operations. Regular expression syntax supported is a subset of CPython re module (and actually is a subset of POSIX extended regular expressions).

Supported operators are:

'.'

Match any character.

'[]'

Match set of characters. Individual characters and ranges are supported.

'^'

'$'

'?'

'*'

'+'

'??'

'*?'

'+?'

Counted repetitions ({m,n}), more advanced assertions, names groups, etc. are not supported.

.. function:: compile(regex)

   Compile regular expression, return ``regex`` object.

.. function:: match(regex, string)

   Match ``regex`` against ``string``. Match always happens from starting
   position in a string.

.. function:: search(regex, string)

   Search ``regex`` in a ``string``. Unlike ``match``, this will search
   string for first position which matches regex (which still may be
   0 if regex is anchored).

.. data:: DEBUG

   Flag value, display debug information about compiled expression.

Compiled regular expression. Instances of this class are created using ure.compile().

.. method:: regex.match(string)

.. method:: regex.search(string)

.. method:: regex.split(string, max_split=-1)

Match objects as returned by match() and search() methods.

.. method:: match.group([index])

   Only numeric groups are supported.