[gtk-web: 1/2] Added Perl example

[Emmanuele Bassi <ebassi src gnome org>]

commit 7ce85ea4468d1ad8629c173ea75647f7c8342686
Author: Красимир Беров <berov cpan org>
Date:   Sun Mar 22 22:06:35 2020 +0200

    Added Perl example

 _data/sample_codes.yml | 31 +++++++++++++++++++++++++++++++
 1 file changed, 31 insertions(+)
---
diff --git a/_data/sample_codes.yml b/_data/sample_codes.yml
index 594bbe5..dce34a6 100644
--- a/_data/sample_codes.yml
+++ b/_data/sample_codes.yml
@@ -134,3 +134,34 @@ codes:
         return g_application_run (G_APPLICATION (app), argc, argv);
       }
       ```
+  - name: Perl
+    ext: pl
+    snippet: |
+      ```perl
+      #!/usr/bin/env perl
+      use strict; use warnings; use utf8;
+      use Glib::IO;
+      use Gtk3;
+
+      # Create a new application
+      my $app =
+        Gtk3::Application->new('com.example.Gtk3Application', 'G_APPLICATION_FLAGS_NONE');
+
+      # When the application is launched…
+      $app->signal_connect(
+        activate => sub {
+          my $app = shift;
+          # … create a new window …
+          my $win = Gtk3::ApplicationWindow->new($app);
+          # … with a button in it …
+          my $btn = Gtk3::Button->new('Hello World!');
+          # … which closes the window when clicked
+          $btn->signal_connect(clicked => sub { $win->destroy });
+          $win->add($btn);
+          $win->show_all();
+        }
+      );
+
+      # Run the application
+      $app->run(\@ARGV);
+      ```