lambda and for that matter goto not forgetting sugar

[Nick Coghlan]

Philip Smith wrote:
> I've read with interest the continuing debate about 'lambda' and its place 
> in Python.
> 
> Just to say that personally I think its an elegant and useful construct for 
> many types of programming task (particularly number theory/artificial 
> intelligence/genetic algorithms)
> 
> I can't think why anyone would be proposing to do away with it.  Sometimes 
> an anonymous function is just what you need and surely it just reflects the 
> python philosophy of everything being an object (in this case a code 
> object).

The *concept* is fine, but the current syntax is seriously ugly, and the keyword 
used creates false expectations for those familiar with what lambda calculus 
actually *is*.

If the lambda syntax were a new proposal to be added to the language now, it 
would never be accepted.

Unfortunately, its existence tends to stymie efforts to come up with a 
*Pythonic* way of spelling the same idea. The people who want to get rid of 
lambda completely think coming up with a new spelling is a waste of time - "Just 
define the damn function already!" is their rallying cry. The people who want 
real lambda calculus complain that they still can't put statements inside 
expressions - they shout "Give me real anonymous functions, not this neutered 
junk that restricts me to a single expression!". And, of course, there's always 
someone to complain that supporting a new spelling would violate TOOWTDI - "But, 
but, we already have def and lambda, why are you trying to come up with yet 
another way to create a function?".

Anyway, check out AlternateLambdaSyntax on the python.org Wiki if you haven't 
already. For my own part, I'd like a new spelling. Something that is more 
stylistically in line with a genexp would be significantly preferable to the 
status quo (e.g "(x*x from (x))" aligns better with "(x*x for x in seq)" than 
"lambda x: x*x" does).

> Following on naturally from that last point I would also like to 'deprecate' 
> the use of the expression 'syntactic sugar' on these pages.  All high level 
> languages (Python included) are nothing but syntactic sugar designed to 
> conceal the ugliness of what actually gets sent to the CPU to make it all 
> happen.

Yup, you're right. But 'syntactic sugar' often isn't used in a negative way - 
it's more descriptive than anything. It's any language change that's designed to 
make common idioms easier to use.

Cheers,
Nick.
No comment on the goto thing ;)

-- 
Nick Coghlan   |   ncoghlan at email.com   |   Brisbane, Australia
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