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Date: Thu, 31 Jul 2025 09:10:18 +0200
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Subject: Re: [PHP-DEV] [RFC] Optional Catch Block Body
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From: rob@bottled.codes ("Rob Landers")

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On Thu, Jul 31, 2025, at 06:53, Mihail Liahimov wrote:
> Introduction
>=20
> Currently, PHP requires a block body for catch clauses even when the c=
aught exception is not used. This results in unnecessary boilerplate cod=
e. This RFC proposes allowing catch clauses without a body when the exce=
ption variable is omitted.
>=20
> Proposal
>=20
> Allow the following syntax where the curly braces can be omitted when =
no exception variable is specified and no handling is needed:
>=20
> try {
>     // code that may throw
> } catch (SomeError);
>=20
> This would be equivalent to:
>=20
> try {
>     // code that may throw
> } catch (SomeError) {}
>=20
> Motivation
>=20
> Reduced Boilerplate: Eliminates unnecessary empty blocks when exceptio=
ns only need to be caught and ignored.
> Improved Readability: Makes the code more concise and focuses on the i=
mportant parts.
>=20
> Backward Incompatible Changes
>=20
> None. This is purely an additive change to the syntax.

I can see something like this being useful in niche applications. For ex=
ample, I have a proxy generation class that creates something like this:

public function remoteCall() {
  $this->operation =3D nameof($this->remoteCall(...));
  $this->arguments =3D func_get_args();
  throw new SpecialException();
}

This SpecialException gets caught to let me know the application has con=
sumed the one-use proxy. Using it looks something like=20

rpc(fn(RemoteObject $o) =3D> $o->remoteCall());

which just provides type-safe rpc at the expense of some boilerplate.

I also use empty exceptions to "jump" the stack when my framework knows =
there is nothing more to do until outside events happen. I think I could=
 probably use fibers to do the same, but if the user is using a fiber li=
brary; there is no guarantee they'll play nice together. This is true wi=
th exceptions as well, but the user has direct control over exceptions (=
do not catch Throwable, for instance).

That being said, I'm doing niche things. Outside of this framework/SDK, =
I have not ever really used empty catches, and even in my case, my empty=
 catches have lengthy comments describing why they are empty in case a u=
ser steps into it, so they can better understand how the framework works.

=E2=80=94 Rob
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<!DOCTYPE html><html><head><title></title></head><body><div>On Thu, Jul =
31, 2025, at 06:53, Mihail Liahimov wrote:</div><blockquote type=3D"cite=
" id=3D"qt" style=3D""><div dir=3D"ltr"><div>Introduction</div><div><br>=
</div><div>Currently, PHP requires a block body for catch clauses even w=
hen the caught exception is not used. This results in unnecessary boiler=
plate code. This RFC proposes allowing catch clauses without a body when=
 the exception variable is omitted.</div><div><br></div><div>Proposal</d=
iv><div><br></div><div>Allow the following syntax where the curly braces=
 can be omitted when no exception variable is specified and no handling =
is needed:</div><div><br></div><div>try {</div><div>&nbsp; &nbsp; // cod=
e that may throw</div><div>} catch (SomeError);</div><div><br></div><div=
>This would be equivalent to:</div><div><br></div><div>try {</div><div>&=
nbsp; &nbsp; // code that may throw</div><div>} catch (SomeError) {}</di=
v><div><br></div><div>Motivation</div><div><br></div><div>Reduced Boiler=
plate: Eliminates unnecessary empty blocks when exceptions only need to =
be caught and ignored.</div><div>Improved Readability: Makes the code mo=
re concise and focuses on the important parts.</div><div><br></div><div>=
Backward Incompatible Changes</div><div><br></div><div>None. This is pur=
ely an additive change to the syntax.</div></div></blockquote><div><br><=
/div><div>I can see something like this being useful in niche applicatio=
ns. For example, I have a proxy generation class that creates something =
like this:</div><div><br></div><div>public function remoteCall() {</div>=
<div>&nbsp; $this-&gt;operation =3D nameof($this-&gt;remoteCall(...));</=
div><div>&nbsp; $this-&gt;arguments =3D func_get_args();</div><div>&nbsp=
; throw new SpecialException();</div><div>}</div><div><br></div><div>Thi=
s SpecialException gets caught to let me know the application has consum=
ed the one-use proxy. Using it looks something like </div><div><br></div=
><div>rpc(fn(RemoteObject $o) =3D&gt; $o-&gt;remoteCall());</div><div><b=
r></div><div>which just provides type-safe rpc at the expense of some bo=
ilerplate.</div><div><br></div><div>I also use empty exceptions to "jump=
" the stack when my framework knows there is nothing more to do until ou=
tside events happen. I think I could probably use fibers to do the same,=
 but if the user is using a fiber library; there is no guarantee they'll=
 play nice together. This is true with exceptions as well, but the user =
has direct control over exceptions (do not catch Throwable, for instance=
).</div><div><br></div><div>That being said, I'm doing niche things. Out=
side of this framework/SDK, I have not ever really used empty catches, a=
nd even in my case, my empty catches have lengthy comments describing wh=
y they are empty in case a user steps into it, so they can better unders=
tand how the framework works.</div><div><br></div><div id=3D"sig12122915=
2">=E2=80=94 Rob</div></body></html>
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