On Thu, Feb 11, 2021 at 8:58 PM Random832 <random...@fastmail.com> wrote:
> On Thu, Feb 11, 2021, at 06:48, Paul Sokolovsky wrote:
> > Hello,
> >
> > On Thu, 11 Feb 2021 12:24:55 +0100
> > "J. Pic" <j...@yourlabs.org> wrote:
> >
> > > Hi all,
> > >
> > > Lambdas can be defined as such:
> > >
> > > w = lambda: [12]
> > > x = lambda y: len(y)
> > >
> > > I'd like to propose the following:
> > >
> > > w = (): [12]
> >
> > What will be the meaning of {(): [12]} ? Hint: it will be a dictionary
> > of empty tuple mapping to a list, where do you see lambda here?
>
> This could be solved with parentheses, but I think it'd probably be better
> to use similar syntax to C#, Java, and Javascript instead, and use () ->
> [12] or () => 12...
>
Agreed. I'd prefer the JavaScript solution, since -> already has a
different meaning in Python return *type*. We could use -> to simplify
typing.Callable, and => to simplify lambda.
> It's worth noting that all three of these are later additions to their
> respective languages, and they all have earlier, more difficult, ways of
> writing nested functions within expressions. Their designers saw the
> benefit of an easy lambda syntax, why don't we?
>
Probably we were blinded by the endless search for for multi-line lambdas.
It's not too late.
> It also may be worth looking at what it would take to allow asynchronous
> lambdas. Syntactically, while "any lambda containing await" is tempting,
> the lack of static typing means that we need a way to specify async lambdas
> that do not contain await. Javascript prefixes the argument list with async
> [i.e. "async () => ..." or "async onearg => ..."], as does C# even though
> it could in principle get away without doing so because of static typing.
>
Makes sense.
--
--Guido van Rossum (python.org/~guido)
*Pronouns: he/him **(why is my pronoun here?)*
<http://feministing.com/2015/02/03/how-using-they-as-a-singular-pronoun-can-change-the-world/>
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