[Perl5-syntax] Syntax/implementation for try/catch

[Ash Berlin]

On 13 Jan 2009, at 19:26, Ash Berlin wrote:

> So eval sucks. I want proper try catch semantics. Some thing like  
> this:
>
> sub foo {
>  my ($self) = @_;
>  try {
>    $self->some_call_that_dies;
>    return (qw/return value from foo/);
>  }
>  catch (My::Error $e where { $_->code >= 400 } ) {
>    print("got My::Error code " . $e->code . "\n");
>  }
>  catch (Str $e) {
>    print("Got str error: $e\n");
>  }
>  catch ($e) {
>    print("Got unknown error: $e\n");
>  }
>  # $@ will be undef/previous value here.
> }
>

Oh yeah, and my current thinking is that this gets turned into:

sub foo {
   try(sub {
     $self->some_call_that_dies;
     return (qw/return value from foo/);
  },
  $state_obj, sub{
    print("got My::Error code " . $e->code . "\n");
  },
  $state_obj2, sub {
    print("Got str error: $e\n");
  },
  $state_obj3, sub {
    print("Got unknown error: $e\n");
  });
  # $@ will be undef/previous value here.
}

I haven't work out exactly what i'll Devel::Declare it into, but thats  
a relatively minor detail once i've got the return issue sorted.