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Date: Wed, 19 Mar 2025 13:51:03 +0200
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Subject: Re: [PHP-DEV] PHP True Async RFC - Stage 2
To: Rob Landers <rob@bottled.codes>
Cc: internals@lists.php.net
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From: edmond.ht@gmail.com (Edmond Dantes)

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>
>  Generally, RFCs are for changes in the language itself, not for API
contracts in C. That can generally be handled in PRs, if I understand
correctly.
>

I thought this was handled by PHP INTERNAL.
So I have no idea how it actually works.

>
>  or other weird shenanigans? I think it would be better as a statement.
>
Your example was absolutely convincing.
I have nothing to argue with :)
So, `suspend` is 100% an operator.

>
>  What happens if it throws? Why does it return NULL; why not `void` or
the result of the awaited spawn?
>
Exceptions are thrown if they exist. This also applies to `suspend`, by the
way.

Why not `void`?
Because the expression `$result =3D await ...` must resolve to something.

If I remember the core code correctly, the PHP engine returns `NULL` even
if the function is declared as `void`.

>
>  Wouldn't it be better to throw an exception instead of silently failing?
>
Possibly, yes.
For me, this is a difficult situation because the code inside the final
handler is already executing in a context where any exception can interrupt
it.

>
>  Hmm. Do you mean this literally? So if I call a random function via
spawn, it will have access to my current scope?
>
Exactly.
And yes, accessing a `Scope` defined in a different context is like
shooting yourself in the foot.
That's why this possibility should be removed.

>
>  I know I have been critical in this email, but I actually like it; for
the most part. I think there are still some rough edges to sand down and
polish, but it is on the right track!
>

In this RFC, I made two very big mistakes due to attention distortion.
This once again proves that it should be moved forward very slowly, as it
only seems simple.

The first major mistake was that I tried to make functions an element of
structural concurrency.
But to do so, functions would need to have an `async` attribute, which
contradicts the RFC.

The second mistake is the `currentScope()` function, which doesn't just
shoot you in the foot=E2=80=94it shoots you straight in the head (just like
`globalScope()`).
Of course, a programmer can intentionally pass the `$scope` object to
another coroutine, but making it easier for them to do so is madness.

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<div dir=3D"ltr">&gt;<br>&gt;=C2=A0

Generally, RFCs are for changes in the language itself, not for API contrac=
ts in C. That can generally be handled in PRs, if I understand correctly.<b=
r>&gt;<div><br></div><div>I thought this was handled by PHP INTERNAL. =C2=
=A0<br>So I have no idea how it actually works.=C2=A0=C2=A0<br></div><div><=
br></div><div>&gt;<br>&gt;=C2=A0

or other weird shenanigans? I think it would be better as a statement.<br>&=
gt;</div><div>Your example was absolutely convincing. =C2=A0<br>I have noth=
ing to argue with :) =C2=A0<br>So, `suspend` is 100% an operator.=C2=A0=C2=
=A0<br></div><div><br></div><div>&gt;<br>&gt;=C2=A0

What happens if it throws? Why does it return NULL; why not `void` or the r=
esult of the awaited spawn?<br>&gt;</div><div>Exceptions are thrown if they=
 exist. This also applies to `suspend`, by the way. =C2=A0<br><br>Why not `=
void`? =C2=A0<br>Because the expression `$result =3D await ...` must resolv=
e to something. =C2=A0<br><br>If I remember the core code correctly, the PH=
P engine returns `NULL` even if the function is declared as `void`.=C2=A0=
=C2=A0<br></div><div><br></div><div>&gt;<br>&gt;=C2=A0

Wouldn&#39;t it be better to throw an exception instead of silently failing=
?<br>&gt;</div><div>Possibly, yes. =C2=A0<br>For me, this is a difficult si=
tuation because the code inside the final handler is already executing in a=
 context where any exception can interrupt it.=C2=A0=C2=A0<br></div><div><b=
r></div><div>&gt;<br>&gt;=C2=A0

Hmm. Do you mean this literally? So if I call a random function via spawn, =
it will have access to my current scope?<br>&gt;</div><div>Exactly. =C2=A0<=
br>And yes, accessing a `Scope` defined in a different context is like shoo=
ting yourself in the foot. =C2=A0<br>That&#39;s why this possibility should=
 be removed.=C2=A0=C2=A0<br></div><div><br></div><div>&gt;<br>&gt;=C2=A0

I know I have been critical in this email, but I actually like it; for the =
most part. I think there are still some rough edges to sand down and polish=
, but it is on the right track!<br>&gt;</div><div><br></div><div>In this RF=
C, I made two very big mistakes due to attention distortion. =C2=A0<br>This=
 once again proves that it should be moved forward very slowly, as it only =
seems simple. =C2=A0<br><br>The first major mistake was that I tried to mak=
e functions an element of structural concurrency. =C2=A0<br>But to do so, f=
unctions would need to have an `async` attribute, which contradicts the RFC=
. =C2=A0<br><br>The second mistake is the `currentScope()` function, which =
doesn&#39;t just shoot you in the foot=E2=80=94it shoots you straight in th=
e head (just like `globalScope()`). =C2=A0<br>Of course, a programmer can i=
ntentionally pass the `$scope` object to another coroutine, but making it e=
asier for them to do so is madness.=C2=A0</div></div>

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