pep 308: why doing (almost) nothing suffices

[Steven Taschuk]

Quoth Edward K. Ream:
  [...]
> def choose_eval(cond, a, b): # warning: evals all arguments
> 
>     if cond: return eval(a)
>     else: return eval(b)
> 
> Heavy duty stuff by my present bathtub standards.  So to "delay" the
> evaluation of an argument, just quote it.  Wow--just like lithp.  Example:
> 
> choose_eval(a < b,"foo(a)","spam(b)")

Hm.  What about this little problem?

    >>> def optional_reverse(s, reverse=0):
    ...     return choose_eval(reverse, 's.reverse()', 's')
    ... 
    >>> optional_reverse('foo', 1)
    [...]
    NameError: name 's' is not defined

I suppose choose_eval could be special-cased to take implicit
arguments of the locals and globals of the calling context...

  [...]
> P.P.S. All criticisms of this brilliant proposal are obviously impertinent,
> even if valid.

I am ashamed.  Forgive me!

-- 
Steven Taschuk                                                 o- @
staschuk at telusplanet.net                                      7O   )
                                                               "  (