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From: Ian Kelly <ian.g.kelly@gmail.com>
Date: Wed, 11 Feb 2015 19:57:20 -0700
Subject: Re: Alternative to multi-line lambdas: Assign-anywhere def statements
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On Wed, Feb 11, 2015 at 7:06 PM, Terry Reedy <tjreedy@udel.edu> wrote:
>> I can't see why the parser would understand more easily
>>
>> def f(x):
>>      return x**2
>> than
>>
>> f = x->
>>      return x**2
>
>
> The parser parses both equally well.  That is not the issue.

The compiler could at some point recognize that the function is being
assigned to a simple name and transform the assignment into a def for
purposes of byte code generation. It could also do the same with
lambda, although it currently doesn't.

The reason I don't like this replacing def isn't because the name is
necessarily lost. It's because the lack of the well-defined def
statement encourages more complex usages like

    functions['f'] = x -> x**2

where such implicit transformations won't work.