Hello

Giving a script as simple as this

use strict;
use warnings;
use utf8;
use Tk;

my $mw = tkinit();
my $name = 'bound to entry';
my $label = $mw->Label(
    -text => 'Enter:',
)->grid(
    -row => 0,
    -column => 0,
);
my $entry = $mw->Entry(
    -textvariable => \$name
)->grid(
    -row => 0,
    -column => 1,
);
my $button = $mw->Button(
    -text => 'Clear',
    -command => sub{
        $name = '';
    },
)->grid(
    -row => 2,
    -column => 0,
    -columnspan => 2,
);
$mw->MainLoop();

[download]

how can a call a subroutine if $name is programmatically changed? (In this case by clicking of the button, but in my real case it is changed from a third party component.

In reply to call subroutine if scalar is changed by Anonymous Monk

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