Re: Re: Re: Re: Context aware functions - best practices?

[demerphq]

Well theres three possibilities.... First one is just let Perl throw an exception when it tries to use the value in the wrong way. Second is to replace the test code with something that checks that the item ISA correct type, instead of checking if the type is ARRAY.

UNIVERSAL::isa($array_ref,"ARRAY") 
      or die "Can't use anything but an array";

However this is still not an exhaustive check as it will fail if some moron does

my $array_ref=bless {},"ARRAY";

Which is a case where afaik only perl itself can tell the difference.

The third option is I guess the most paranoid and would be something like:

eval{ ref($arrayref) and @$arrayref ? 1 : 1 } 
  or die "Must have a reference to something that behaves like an ARRA
+Y.\n".
         "Failed to coerce '$arrayref': $@";

So personally I would just let my code choke and have the end user track the problem down. (This assumes that I have already sufficient regression test to ensure that my code is not in error in the first place ;-)

--- demerphq
my friends call me, usually because I'm late....