Hi,

I often find myself having to check a long list of variables for defined- and non-zero-ness. For debugging purposes it would have been helpful to print the name of the variable that were undef or empty. 

#!/usr/bin/perl
use strict;
use warnings;

#######################################################
# Input: list of scalars.
# Return: 1 if all scalars are defined and non-empty,
# otherwise undef.
sub defnz  {
#######################################################
    for my $item (@_) {
        if (!defined($item)) {
            print STDERR "not defined\n";
            return;
        } elsif ($item eq '') {
            print STDERR "empty\n";
            return;
        }
    }
    print STDOUT "All scalars defined and non-empty\n";
    return 1; # all items in list defined and non-empty
}


my ($foo,$bar,$baz) = ("FOO","BAR","BAZ");
defnz($foo,$bar,$baz);
($foo,$bar,$baz) = ("FOO","BAR","");
defnz($foo,$bar,$baz);
($foo,$bar,$baz) = ("FOO",undef,"");
defnz($foo,$bar,$baz);

__END__

[download]
Above sample code outputs: 
All scalars defined and non-empty
empty
not defined

[download]
I would want it to output: 
All scalars defined and non-empty
'$baz' empty
'$bar' not defined

[download]
Is there a way to access variable names like this?

Best regards,
Andreas
--

In reply to Access variable names by andreas1234567

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