in reply to Access variable names

There might be better ways to do this. Here is one way (not very clean tho) 


use strict;
use warnings;

my $x = 10; 
my $y = undef; 
my $check = '$x,$y'; 
my @vars = split /,/,$check; 
for (@vars) { 
    if (defined(eval($_))) { 
        print "$_ = Defined\n"; 
    } else { print "$_ = Not defined\n";}
}
__END__
$x = Defined
$y = Not defined

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There are risks associated with eval so you need to watch out

cheers

SK

Replies are listed 'Best First'.
Re^2: Access variable names
by andreas1234567 (Vicar) on Sep 01, 2005 at 12:09 UTC
    Thanks! That was a cool solution. One caveat though, the variables to be checked must be visible (scope-wise) to the eval: 
    use strict;
use warnings;
 
my $foo = "1";
my $bar = "42";
 
my $defnz = sub {
  for (@_) {
    if (!defined(eval($_))) {
      print "$_ undef!";
      return;
    } elsif (eval($_) eq '') {
      print STDERR "$_ empty!";
      return;
    }
  }
  return 1;
};
 
my $baz = "101";
 
print "ok1\n" if &$defnz(split /,/,q($foo,$bar));
print "ok2\n" if &$defnz(split /,/,q($foo,$bar,$baz));
 
__END__
ok1
$baz undef!

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