I have tried everything I can think of (plus a tonne of random experiments) to assign $_ within the foreach statement to a hash. I know that you can assign it after the foreach line, but I have a very particular code limitation which doesn't allow me to do this.

#!/usr/bin/perl -s

use strict;
use Data::Dumper;

my @x = qw(a c e g);
my $var = {'a'=>"z", 'b'=>"y", 'c'=>"x", 'd'=>"w", 'e'=>"v", 'f'=>"u",
+ 'g'=>"t", 'h'=>"s"};
my $y = "e";
foreach $var->{$y} (@x){
    print "$y = $var->{$y}\n";
    $y = $var->{$y};
}

die Dumper($var);
[download]

What I think is happening is the perl compiler cannot handle '{' and '}' characters in the position where it is looking for $VAR to assign $_ to. When I run the code not only do I get an error about the foreach line, but I also get a syntax error about the print line where there is no syntax error.

syntax error at ./foreach2var.pl line 9, near "$var->"
syntax error at ./foreach2var.pl line 12, near "}"
Execution of ./foreach2var.pl aborted due to compilation errors.
[download]

Is there any way to assign $_ within the foreach statement directly to a hash reference rather than assigning it with $var->{$y} = $_; on the following line?

I am looking for the following output

e = a
a = c
c = e
e = g
$VAR1 = {
          'e' => 'g',
          'a' => 'c',
          'd' => 'w',
          'c' => 'e',
          'h' => 's',
          'b' => 'y',
          'g' => 't',
          'f' => 'u'
        };
[download]

Also, I am aware that the following works, but again, I have a particular code limitation which means I have to be able to handle foreach statements

#!/usr/bin/perl -s

use strict;
use Data::Dumper;

my @x = qw(a c e g);
my $var = {'a'=>"z", 'b'=>"y", 'c'=>"x", 'd'=>"w", 'e'=>"v", 'f'=>"u",
+ 'g'=>"t", 'h'=>"s"};
my $y = "e";
while($var->{$y} = shift @x){
    print "$y = $var->{$y}\n";
    $y = $var->{$y};
}

die Dumper($var);
[download]

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