In the code below I would like the Hash filled in the subroutine FillHashOne() to be accessible as a reference in $Hash. However all I get is an empty hash ref.
I think I am missing the section of my brain that is needed to understand references. I have read all the tutorials and have used references many times, but then I run into a situation like this that stymies me.
All help and suggestions are appreciated!
Update: Duh! I messed up my closure and had it inside the subroutine. It works when I fixed that.
#!/usr/bin/perl
use strict;
use warnings;
use constant false => 0;
use constant true => 1;
$| = true;
use Data::Dumper;
my $Hash = {};
sub FillHashOne
{
my %HashOne;
{
my ($Key, $Value) = @_;
if(!defined($Key))
{
return(\%HashOne);
}
else
{
$HashOne{$Key} = $Value;
}
}
}
$Data::Dumper::Indent = 3;
$Data::Dumper::Purity = true;
$Data::Dumper::Varname = 'Hash';
$Data::Dumper::Quotekeys = true;
$Hash->{'One'} = 1;
$Hash->{'Two'} = 2;
$Hash->{'Three'} = 3;
$Hash->{'String'} = 'Foo Bar';
print __LINE__ . ":Main:\$Hash:\n" . Dumper($Hash);
for (my $i = 0; $i < 10; $i++)
{
FillHashOne($i, "Value:\[$i\]");
}
$Hash->{'HashOne'} = FillHashOne(undef());
print __LINE__ . ":Main:\$Hash:\n" . Dumper($Hash);
Updated Code:
#!/usr/bin/perl
use strict;
use warnings;
use constant false => 0;
use constant true => 1;
$| = true;
use Data::Dumper;
my $Hash = {};
{
my %HashOne;
sub FillHashOne
{
my ($Key, $Value) = @_;
if(!defined($Key))
{
return(\%HashOne);
}
else
{
$HashOne{$Key} = $Value;
}
}
}
$Data::Dumper::Indent = 3;
$Data::Dumper::Purity = true;
$Data::Dumper::Varname = 'Hash';
$Data::Dumper::Quotekeys = true;
$Hash->{'One'} = 1;
$Hash->{'Two'} = 2;
$Hash->{'Three'} = 3;
$Hash->{'String'} = 'Foo Bar';
print __LINE__ . ":Main:\$Hash:\n" . Dumper($Hash);
for (my $i = 0; $i < 10; $i++)
{
FillHashOne($i, "Value:\[$i\]");
}
$Hash->{'HashOne'} = FillHashOne(undef());
print __LINE__ . ":Main:\$Hash:\n" . Dumper($Hash);
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