Carel Fellinger cfelling at iae.nl
Thu Jul 12 10:37:46 EDT 2001

Michael Chermside <mcherm at destiny.com> wrote:
>>>> class Eval:
> def __getitem__(self, key):
> 		return eval(key)


> Now THAT'S a wierd-but-cool hack! Very powerful and flexible, and
> simple enough to use. It should definitely be added to the cookbook. 
> It does, unfortunately, have one significant limitation: the expression
> cannot contain the character ")", which is one you'd like to use in
> expressions.

You can, but it has to match opening braces. The thing that is impossible
is to have strings inside the expression that have extra closing braces.

>>> "%((1+2)*(3+3))s" % Eval()
>>> "%('a'*2)s" % Eval()
>>> "%('a)'*2)s" % Eval()
Traceback (innermost last):
  File "<stdin>", line 1, in ?
  File "<stdin>", line 3, in __getitem__
  File "<string>", line 1
SyntaxError: invalid token

groetjes, carel

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