Only test on Perl 5.30. Add compat::p7 to lib

.travis.yml

@@ -3,22 +3,6 @@ language: perl
 matrix:
   include:
   - perl: "5.30"
-  - perl: "5.28"
-  - perl: "5.26"
-  - perl: "5.24"
-  - perl: "5.22"
-  - perl: "5.20"
-    dist: trusty
-  - perl: "5.18"
-    dist: trusty
-  - perl: "5.16"
-    dist: trusty
-  - perl: "5.14"
-    dist: trusty
-  - perl: "5.12"
-    dist: trusty
-  - perl: "5.10"
-    dist: trusty
 
 before_install:
   - sudo apt-get install libinline-perl libogg-dev libvorbis-dev

lib/compat/perl7.pm

@@ -0,0 +1,49 @@
+=head1 compat::perl7
+
+=head2 Subroutines
+
+=head3 import
+
+Do the clever stuff.
+
+=cut
+
+package compat::perl7;
+
+# use compat::perl7 enables perl 5 code to function in a perl 7-ish way as much as possible compared to the version you are running.
+# it also is a hint to both tools and the compiler what the level of compatibility is with future versions of the language.
+
+BEGIN {
+    # This code is a proof of concept provided against 5.30. In order for this code to work on other versions of perl
+    # we would need to generate it via p7.pm.PL as part of shipping it to CPAN.
+    $] >= 5.030 && $] < 5.031 or die("Perl 5.30 is required to use this module.");
+}
+
+sub import {
+
+    # use warnings; no warnings qw/experimental/;
+    # perl -e'use warnings; no warnings qw/experimental/;  my $w; BEGIN {$w = ${^WARNING_BITS} } print unpack("H*", $w) . "\n"'
+    ${^WARNING_BITS} = pack( "H*", "55555555555555555555555515000440050454" );
+
+    # use strict; use utf8;
+    # perl  -MData::Dumper -e'my $h; use strict; use utf8; use feature (qw/bitwise current_sub declared_refs evalbytes fc postderef_qq refaliasing say signatures state switch unicode_eval unicode_strings/); BEGIN {  $h = $^H } printf("\$^H = 0x%08X\n", $h); print Dumper \%^H; '
+    $^H = 0x1C820FE2;
+
+    %^H = (
+        'feature___SUB__'      => 1,
+        'feature_bitwise'      => 1,
+        'feature_evalbytes'    => 1,
+        'feature_fc'           => 1,
+        'feature_myref'        => 1,
+        'feature_postderef_qq' => 1,
+        'feature_refaliasing'  => 1,
+        'feature_say'          => 1,
+        'feature_signatures'   => 1,
+        'feature_state'        => 1,
+        'feature_switch'       => 1,
+        'feature_unicode'      => 1,
+        'feature_unieval'      => 1
+    );
+}
+
+1;