Devel::StrictMode - determine whether strict (but slow) tests should be enabled

       Toby Inkster <tobyink@cpan.org>.

       Please report any bugs to <http://rt.cpan.org/Dist/Display.html?Queue=Devel-StrictMode>.

       This software is copyright (c) 2014 by Toby Inkster.

       This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5
       programming language system itself.

       This module provides you with a constant "STRICT" which you can use to determine whether additional
       strict (but slow) runtime tests are executed by your code.

       "STRICT" is true if any of the following environment variables have been set to true:

          PERL_STRICT
          EXTENDED_TESTING
          AUTHOR_TESTING
          RELEASE_TESTING

       "STRICT" is false otherwise.

       It is anticipated that you might set one or more of the above variables to true while running your test
       suite, but leave them all false in your production scenario.

       Although not exported by default, a constant "LAX" is also provided, which returns the opposite of
       "STRICT".

   UsingSTRICTwithMoose/Moo/Mouseattributes
       Type constraint checks ("isa") are conducted at run time. Slow checks can slow down your constructor and
       accessors. As shown above, "STRICT" can be used to alternate between a slower by stricter type constraint
       check, and a faster but looser one.

       Don't try this if your attribute coerces. It will subtly break things.

   UsingSTRICTtoperformassertionsinfunctionandmethodcalls
       You may protect blocks of assertions with an "if (STRICT) { ... }" conditional to ensure that they only
       run in your testing environment.

          sub fibonacci
          {
             my $n = $_[0];

             if (STRICT)
             {
                die "expected exactly one argument"
                   unless @_ == 1;
                die "expected argument to be a natural number"
                   unless $n =~ /\A[0-9]+\z/;
             }

             $n < 2 ? $n : fibonacci($n-1)+fibonacci($n-2);
          }

       Because "STRICT" is a constant, the Perl compiler will completely optimize away the "if" block when
       running in your production environment.

   UsingSTRICTwithpragmata
       Thanks to if it's easy to use "STRICT" to conditionally load pragmata.

          use Devel::StrictMode;

          use strict;
          use warnings STRICT ? qw(FATAL all) : qw(all);

          no if STRICT, "bareword::filehandles";
          no if STRICT, "autovivification";

       See also autovivification, bareword::filehandles, indirect, multidimensional, etc.

       THIS PACKAGE IS PROVIDED "AS IS" AND WITHOUT ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, WITHOUT
       LIMITATION, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.

perl v5.40.1                                       2025-08-09                             Devel::StrictMode(3pm)

       Devel::StrictMode - determine whether strict (but slow) tests should be enabled

       strictures.

          package MyClass;

          use Moose;
          use Devel::StrictMode;

          has input_data => (
             is       => 'ro',
             isa      => STRICT ? "HashRef[ArrayRef[Str]]" : "HashRef",
             required => 1,
          );