The problem is, the scalar of an array IS just a plain old scalar. You can't expect to tell the difference between the size of an array (such as '3'), and a plain old number (such as '3'). And your function really shouldn't care how the caller came up with the parameter it passed you.

If you expect an integer from 1 to 5, and you are passed the scalar of an array that happens to have between 1 and 5 elements, that is hardly wrong. It may just be a fancy way of counting widgets.

use strict;
use warnings;
use Carp;

use constant BAR => 3.14159265;

my @list = ('p','i','e');
taster(BAR);
taster(22/7);
taster("constant");
taster(\@list);
taster(@list);
taster(scalar @list);

sub taster
{
    my $p1 = shift;
    carp "Hey, that's too many parameters!" if @_;
    print "Ref of $p1 is '".(ref $p1)."'\n";
}

[download]
Gives
Ref of 3.14159265 is ''
Ref of 3.14285714285714 is ''
Ref of constant is ''
Ref of ARRAY(0x182af0c) is 'ARRAY'
Hey, that's too many parameters! at test.pl line 18
        main::taster('p', 'i', 'e') called at test.pl line 12
Ref of p is ''
Ref of 3 is ''

[download]
- SJ

How to make perldoc.perl.org resizable too!

In reply to Re^5: Prototype for constant items??? by SuicideJunkie
in thread Prototype for constant items??? by LanX

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