Re: Overloading ref() just like ->isa and ->can?

Actually, the best practices recommendation should be:

eval {
    local $SIG{__DIE__};
    $obj->isa( ... );
}
[download]

Otherwise, you will trigger all SIGDIE handlers and, not surprisingly, Test::More has one.

My criteria for good software:

Does it work?
Can someone else come in, make a change, and be reasonably certain no bugs were introduced?

Comment on Re: Overloading ref() just like ->isa and ->can? Download Code

Replies are listed 'Best First'.
Re^2: Overloading ref() just like ->isa and ->can? by ysth (Canon) on Aug 23, 2006 at 01:19 UTC
Otherwise, you will trigger all SIGDIE handlers and, not surprisingly, Test::More has one. Test::Builder, actually. To whit: `$SIG{__DIE__} = sub { # We don't want to muck with death in an eval, but $^S isn't # totally reliable. 5.005_03 and 5.6.1 both do the wrong thing # with it. Instead, we use caller. This also means it runs under # 5.004! my $in_eval = 0; for( my $stack = 1; my $sub = (CORE::caller($stack))[3]; $stack+ ++ ) { $in_eval = 1 if $sub =~ /^\(eval\)/; } $Test_Died = 1 unless $in_eval; };` [download] I'm afraid that eval{} users have to be allowed the ease-of-coding advantage over die-handlers. The whole purpose of eval is to catch an exception; you shouldn't have to go through additional hoops to protect against an exception. Yes, there's a perl design botch, but eval{} shouldn't have to suffer for it. (As far as I know, $^S is working in newer perls, which should make things a little easier.)	[reply] [d/l]

Replies are listed 'Best First'.

Re^2: Overloading ref() just like ->isa and ->can?
by ysth (Canon) on Aug 23, 2006 at 01:19 UTC

Otherwise, you will trigger all SIGDIE handlers and, not surprisingly, Test::More has one.

$SIG{__DIE__} = sub {
    # We don't want to muck with death in an eval, but $^S isn't
    # totally reliable.  5.005_03 and 5.6.1 both do the wrong thing
    # with it.  Instead, we use caller.  This also means it runs under
    # 5.004!
    my $in_eval = 0;
    for( my $stack = 1;  my $sub = (CORE::caller($stack))[3];  $stack+
++ ) {
        $in_eval = 1 if $sub =~ /^\(eval\)/;
    }
    $Test_Died = 1 unless $in_eval;
};
[download]

[reply]
[d/l]