Re: conditional exists

I changed your program slightly, added strict and warnings, corrected the line where @values is set and added sample data:

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


my %hash;
my $l;
my @values;

while (<DATA>)
{
   chomp;
   my ($key, $rest) = split /-/;
   push @{$hash{$key}},$rest;
  
}
$l=14;
  @values= exists $hash{$l} ? @{$hash{$l}}:undef;
{
print "\n Hash Value of 14 : @{$hash{$l}} \n";
}

exit(0);

__DATA__
5-ax
14-vor
65-em
14-auf
14-ab
[download]

When I run this I get the following result:


 Hash Value of 14 : vor auf ab
[download]

which to my eye looks good. What did you expect? If you just want the first value of the array instead of the complete array printed, you could use this for example:

if (exists $hash{$l} and @{$hash{$l}}>0) {
  print "Hash value of $l is $hash{$l}->[0]\n"; #or the short form $ha
+sh{$l}[0]
}
else {
  print "Nothing found for $l\n";
}
[download]

Comment on Re: conditional exists Select or Download Code

Replies are listed 'Best First'.
Re^2: conditional exists by Anonymous Monk on Jul 08, 2009 at 12:48 UTC
if the key exists can i get the values to an array? like `@values= exists $hash{$l} ? @{$hash{$l}}:undef; # where @values will have vor auf ab` [download]	[reply] [d/l]
Re^3: conditional exists by jethro (Monsignor) on Jul 08, 2009 at 12:56 UTC
Yes exactly, in my example script above @values has these values: vor auf ab If in doubt, just check it yourself: `print join('\|',@values),"\n"; #will print "vor\|auf\|ab"` [download]	[reply] [d/l]