[Python-Dev] Extracting variables from string.Template objects

[Isaac Morland]

On Fri, 4 Jan 2008, Aahz wrote:

>> Also, on a related issue, does it make sense to scan the template
>> string for invalid escape sequences in Template.__init__?  For the
>> applications I can imagine of string.Template, I would prefer to get
>> an error upon creating the Template object rather than arbitrarily
>> later when I try to .substitute with it.
>
> No, create an is_valid() method at best.

I'm curious as to why.  Is it to avoid changing the behaviour of existing 
code (i.e., backwards compatibility), or do you see a design problem with 
having the Template constructor reject invalid template strings?

Isaac Morland			CSCF Web Guru
DC 2554C, x36650		WWW Software Specialist