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Date: Thu, 25 Mar 2021 13:14:09 -0400
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To: Rowan Tommins <rowan.collins@gmail.com>
Subject: Re: [PHP-DEV] [RFC] Auto-capture multi-line closures and
 shortfunctions take 2
From: mike@newclarity.net (Mike Schinkel)

> On Mar 25, 2021, at 12:50 PM, Rowan Tommins <rowan.collins@gmail.com> =
wrote:
>=20
> On 25/03/2021 15:02, Mike Schinkel wrote:
>> Can you please clarify why "function(...) use(...) {...}" can't be =
their solution when someone needs by-reference capture?
>=20
>=20
> For the same reason - or lack of reason - why it can't be the solution =
when they need by-value capture. In other words, whatever reason people =
have for wanting this RFC.

Are you proposing auto-capture but one that is note able to change the =
variable's value in the outer scope? =20

Since code is worth 1000 words, here is an example of what I think you =
are saying:

    $x =3D 1;
    example(fn() {
       echo $x; // This would print "1"
       $x =3D 2;
       echo $x; // This would print "2"
    });
    echo $x;  // This would still print "1"

If that is what you are saying =E2=80=94 which I did not get from your =
prior arguments =E2=80=94 then I myself would be fine with "by-value" =
capture.

What I like about the RFC is being able to omit the use(...) when =
referencing (reading) a variable inside the closure that come from the =
outer scope.  But almost all of my use-cases would work fine with =
by-value semantics, and for the rest I could use =
"function(...)use(...){...}."

That said, I again suggest this we could omit the "use" keyword for =
short functions: =20

    // 2nd set of parens acts as an implied "use":
    example( fn()(&$var) =3D> $var =3D value() );

-Mike=