My favourite gotcha with eval is if you set a die handler then the die handler is called even inside the eval! In fact I consider this a bug in perl - as does the author of "perldoc die"

Eg 

$SIG{__DIE__} = sub { print "Caught by die handler: $_[0]"; exit };

eval
{
    die "Oops\n";
};

print "Eval returned error: $@" if $@;

[download]
This prints Caught by die handler: Oops.

The fix goes like this :-

$SIG{__DIE__} = sub { print "Caught by die handler: $_[0]"; exit };

eval
{
    local $SIG{__DIE__};
    die "Oops\n";
};

print "Eval returned error: $@" if $@;
Which returns Eval returned error: Oops as anyone would always want.

In reply to Re: Checking the success of eval by ncw
in thread Checking the success of eval by ton

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