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Python syntax in Lisp and Scheme

David Mertz mertz at gnosis.cx
Fri Oct 17 14:20:30 EDT 2003 
bokr at oz.net (Bengt Richter) wrote previously:
|>Nope.  That's the point of the Y combinator; you don't need a name to do
|>this (just first class anonymous functions).  See, for example:
|>    http://en2.wikipedia.org/wiki/Y_combinator
|I'd call that a specialized syntax, to serve my purposes ;-)

Well... it's specialized.  But it's not a syntax, just a somewhat odd
HOF.  But I would definitely agree that I don't want all my recursion to
be based on anonymous functions.

|>This particular convenience is VERY small.
|That's what I meant by the first line in

Yeah, but I put the 'very' in caps :-).

|the hypothetical version is what you were referring to by 'that way.'

Yeah, sorry about my pronoun.  I meant "can't spell the full suite..."

|>    >>> def ValFactory(x):
|>    ...     def say_val(x=x): return 'My value is %s' % x
|>    ...     return say_val
|Sure. Interesting you chose to use the default-value hack rather than
|a closure ;-). What I had in mind when I pre-agreed was something like
| >>> class SayVal(object):
| ...     def __init__(self, v): self.v=v
| ...     def __call__(self): return 'My value is %s' % self.v

Well... the "default value hack" *IS* a closure.

I know I'm in the minority here, but it feels like more of a hack to me
to make class instances whose (main) purpose is to "act like functions"
(i.e. have custom '.__call__()' methods).  In my mind, when I want a
bunch of related callables, the natural approach is writing a function
factory, not a class.

But either way, Bengt's is another perfectly good spelling for a
collection of callables that allow full suites.  Not being Dutch, I
can't say which one is the "one obvious way."

Yours, David...

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