There's some real food for thought in your replies, thanks.

So if get the point, there is no easy way to test whether something can be treated as a hash ref (for instance) short of trying to do so. So the best way to test is to try and catch any exceptions that indicate failure.

If I want to verify membership in a class, I'd need to do something like: 

# Option 1.
if ( eval { $foo->isa('Some::Class') } ) {
  
  # Do stuff with Some::Class
}

# or Option 2.

use Scalar::Util;

if ( blessed $foo and $foo->isa('Some::Class') ) {
  # Do stuff with Some::Class
}

[download]

Are there any big ugly problems with either option? I've tested both and they seem OK, but there's no point trying to learn a new habbit, if it's a bad one!


TGI says moo

In reply to Re^5: RFC: Perl meta programming by TGI
in thread RFC: Perl meta programming by bennymack

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