[Python-Dev] Extracting variables from string.Template objects (original) (raw)

Aahz aahz at pythoncraft.com
Wed Jan 9 03:09:42 CET 2008

On Fri, Jan 04, 2008, Isaac Morland wrote:

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 isvalid() 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?

Mostly the former, though I'm not sure about the performance implications of scanning on instance creation.

Aahz (aahz at pythoncraft.com) <*> http://www.pythoncraft.com/

Weinberg's Second Law: If builders built buildings the way programmers wrote programs, then the first woodpecker that came along would destroy civilization.

More information about the Python-Dev mailing list