How to escape $ on Python string Template class?

Question

Introduction

The string module has a Template class, that lets you make substitutions in a string using a mapping object, for instance:

>>>          


        

Answer 1

This is a Quick Fix (Using recursion):

def check_substitution(tem, m):
    try:
        string.Template(tem).substitute(m)
    except KeyError:
        return False
    except ValueError:
        return check_substitution(tem.replace('$ ', '$'), m) #strip spaces after $
    return True

I Know its take a longer time if there is more than One Space between $ and var , so you may improve it by using Regular Expression.

EDIT

escaping $ into $$ makes more sense [ Thanks @Pedro ] so you can catch ValueError by this statement:

return check_substitution(tem.replace('$ ', '$$ '), m) #escaping $ by $$