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Date: Tue, 25 Jun 2013 01:49:22 +0200
To: Anthony Ferrara <ircmaxell@gmail.com>
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Subject: =?UTF-8?Q?Re=3A_Announcing_RFC_'Anonymous_Catches'?=
From: joost.koehoorn@gmail.com (Joost Koehoorn)

On 25 juni 2013 at 01:20:04, Anthony =46errara (ircmaxell=40gmail.com) wr=
ote:
Joost,

=46irst off, let me say welcome and thanks for the contribution=21

I have a couple of questions around the intended proposal.

1. How do you plan on handling the case where there are multiple catch bl=
ocks=3F

=C2=A0 =C2=A0 try =7B
=C2=A0 =C2=A0 =C2=A0 =C2=A0 code();
=C2=A0 =C2=A0 =7D catch =7B
=C2=A0 =C2=A0 =C2=A0 =C2=A0 doSomething();
=C2=A0 =C2=A0 =7D catch =7B
=C2=A0 =C2=A0 =C2=A0 =C2=A0 doSomethingElse();
=C2=A0 =C2=A0 =7D
As mentioned as latest sentence in the Proposal chapter, an anonymous cat=
ch can only be used as the latest catch, and there can only be one of the=
m. This is also how my current implementation works.

2. You mention as a benefit =22Better possibilities for static analysis t=
ools=22. Can you elaborate on this=3F I don't see how this sort of a chan=
ge would have any effect (as catch would be the same as the existing =60c=
atch (=5CException =24e)=60)...
It's mostly for finding unused variables. I suppose that static analysers=
 currently ignore unused exception variables, but they don't have to when=
 this is accepted and can properly indicate unused exception variables.

3. What benefit short of not having to type =60(=5CException =24e)=60 wou=
ld this have=3F Populating the symbol table is extremely cheap at this st=
age, because the variable is already compiled in (so no hash table lookup=
 or anything).
Performance wise it's indeed very minor and doesn't really matter. It's m=
ore that you're adding code indicating that only a specific exception is =
used, while that may not really be the case.

Consider Java people --Java has Throwable as the superclass of Exception-=
- they may not know that in PHP 'Exception' is the least-specific type an=
d therefore used as catch-all.

As for leaving of the variable, the type of an exception mostly tells eno=
ugh about what happened (well, it should), so you don't have to inspect t=
he exception's error code/message and thus don't need the exception objec=
t at all.

Additionally, I would recommend changing the version target to 5.NEXT (wh=
ich would be 5.6 in practice).
Done=21



As far as my personal feelings, I'd like to get some other commentary fir=
st.


Thanks again=21=21=21

Anthony