Syntax for one-line "nonymous" functions in "declaration style"

[Alexey Muranov]

On jeu., Mar 28, 2019 at 5:00 PM, python-list-request at python.org wrote:
> 
> So my opinion is that lambda expressions should only be used within 
> larger expressions and never directly bound.
> 
>> It would be however more convenient to be able to write instead just
>> 
>>     f(x) = x*x
> 
> Given my view above, this is, standing alone, strictly an 
> abbreviation of the equivalent def statement.  I am presuming that a 
> proper implementation would result in f.__name__ == 'f'.
> 

No, after some thought, i think it should be an abbreviation of "f = 
lambda x: x*x", f.__name__ would still be '<lambda>'.

But i see your point about never assigning lambdas directly, it makes 
sense.  But sometimes i do assign short lambdas directly to variable.

> Is the convenience and (very low) frequency of applicability worth 
> the inconvenience of confusing the meaning of '=' and complicating 
> the implementation?
> 
>> I do not see any conflicts with the existing syntax.
> 
> It heavily conflicts with existing syntax.  The current meaning of
>   target_expression = object_expression
> is
> 1. Evaluate object_expression in the existing namespace to an object, 
> prior to any new bindings and independent of the target_expression.
> 2. Evaluate target_expression in the existing namespace to one or 
> more targets.
> 3. Bind object to target or iterate target to bind to multiple 
> targets.

I do not thick so.  In "x = 42" the variable x is not evaluated.

All examples of the proposed syntax i can think of are currently 
illegal, so i suppose there is no conflicts. (I would appreciate a 
counterexample, if any.)

Thanks for the reference to PEP 8, this is indeed an argument against.

Alexey.