Question

I have a variable currentUser in a sub routine. It carries through to one subroutine, but does not carry through to another subroutine. How can I pass a variable through multiple subroutines while keeping the value?

sub login {
    &app_header;
    print <<EOF;
<form name="macform" method="POST" enctype="application/x-www-form-urlencoded"       action="$fullurl">
    ...stuff
    EOF  
}

sub html_menu {
    $me = $currentUser;
    print $me;
    print <<EOF;
    <form name="menuform" method="POST" enctype="application/x-www-form-urlencoded"     action="$fullurl">
    ..stuff
    EOF
    &app_list_button;
    print "<br>";
    &app_search_button;
    print "<br>";
    &app_edit_button;
    print "</div>";
}

When I attempt to do the same thing the html_form sub does with currentUser in a new sub called after html_form), the variable does not display as what the user entered during login.

Answer 1

sub first {
    my $currentUser = shift;
    second($currentUser);
}

sub second {
    my $currentUser = shift;
    third($currentUser);
}

…and so on.

Passing a variable as argument is done through the @_ variable. You should not attempt to use global variables, it is not a good way to do it. You can do it like so:

my ($arg1, $arg2, @rest) = @_;

Or by using shift, pop and the other methods of manipulating arrays, like I above used shift.

If you are not already doing so, I recommend very strongly that you use

use strict;
use warnings;

It will help you solve many simple problems.