Re: eval {require module};?

There are some situations (which I do not fully understand) where eval{} can trap an error and yet fail to set $@. However the return value will be undef.

So...

unless( eval { require module; 1 } ) {
  my $err = $@ || 'eval failed but did not return error';
  # do something with $err
}
[download]

Update: instert missing 1.

Comment on Re: eval {require module};? Select or Download Code

Replies are listed 'Best First'.
Re^2: eval {require module};? by nobull (Friar) on Mar 17, 2006 at 17:27 UTC
Many months later I now know how eval{} can fail and yet not set $@. It happens if a DESTROY method called during the stack-unwind also does an eval. `use AtExit; eval { my $q = AtExit->new(sub{eval{}}); die "Oops\n"; }; print $@; # Prints nothing` [download]	[reply] [d/l]
Re^3: eval {require module};? by Anonymous Monk on Mar 17, 2006 at 20:17 UTC
Which means you have to `sub DESTROY{ local $@; eval{...} }` [download] if you want to use eval in DESTROY.	[reply] [d/l]