string_template_newsyntax_BAD.py

#!/usr/bin/env python
# this is all fucked up!
import re
import string

t = string.Template('$var')
print t.patern.patern

#\$(?:
#    (?P<escaped>\$) |
#delimiters
#    (?P<named>[_a-z][_a-z0-9]*)      |
#identifier
#    {(?P<braced>[_a-z][_a-z0-9]*)}   |
#identifier
#    (?P<invalid>)
#ill-formed delimeter exprs
#)


class MyTemplate(string.Template):
    delimeter = '{{'
    pattern = r'''
    \{\{(?:
    (?P<escaped>\{\{)|
    (?P<named>[_a-z][_a-z0-9]*)\}\}|
    (?P<braced>[_a-z][_a-z0-9]*)\}\}|
    (?P<invalid>)
    )
    '''

t = MyTemplate('''
{{{{
{{var}}
''')

print 'MATCHES:',
t.pattern.findall(t.template)
print 'SUBSTITUTED:',
t.safe_substitute(var='replacement')