Sorting operator is now done with a natural sorting algorithm

""" Main class of the TQL database.

"""

import re

import time

from copy import copy

from fnmatch import fnmatch

from functools import partial

import ply.yacc as yacc

                                                ShowOperator, LimitOperator,

                                                SortOperator)

RE_NATURAL_SORTING = re.compile('([0-9]+|[^0-9]+)')

def natural_tag_sorter(tag, obj):

    """ Natural sorter for a tag in an object.

    """

    value = obj.get(tag) if tag in obj else ''

    return tuple(int(x) if x.isdigit() else x

                 for x in RE_NATURAL_SORTING.findall(value))

#

# Response objects:

#

        """ Return a new TqlResponse with objects sorted by provided tag.

        """

        self.fetch(tag)

        sorter = lambda obj: obj.get(tag) if tag in obj else lambda obj: None

        sorter = partial(natural_tag_sorter, tag)

        objects = tuple(sorted(self._objects.itervalues(), key=sorter, reverse=reverse))

        for obj in objects:

            obj.show.add(tag)