fork download 
  1. #!/usr/bin/perl
  2. use strict;
  3. use warnings;
  4.  
  5. my %a = ('a' => 1, 'b' => 2);
  6.  
  7. if (exists $a{'c'}) {
  8.     print "exists before\n";
  9. } else {
  10.     print "not exists before\n";
  11. }
  12.  
  13. if (defined $a{'c'}) {
  14.     print "defined\n";
  15. } else {
  16.     print "not defined\n";
  17. }
  18.  
  19. if (exists $a{'c'}) {
  20.     print "exists after\n";
  21. } else {
  22.     print "not exists after\n";
  23. }
  24.  
  25. for my $i(keys(%a)) {
  26.     print $i . "\n";
  27. }
  28.  
Success #stdin #stdout 0s 3740KB
comments (?)
stdin 
Standard input is empty
stdout 
not exists before
not defined
not exists after
a
b
https://ideone.com/synEH8
language:
Perl (perl 5.28.1)
created:
13 years ago
visibility:
public

Share or Embed source code

Discover > Sphere Engine API

The brand new service which powers Ideone!

Discover > IDE Widget

Widget for compiling and running the source code in a web browser!