B::ConstOptree(3) Optree constant folding for $^O, $^V, and $]


$ perl -MO=ConstOptree -MO=Deparse} -e \
'require ($^O eq "MSWin32" ? "Win32.pm" : "POSIX.pm")'
require 'POSIX.pm';
-e syntax OK


This module propagates constant folding for $^O, $^V, and $] variables by installing custom PL_check handlers for numeric and string comparison opcodes. In the handlers, references to $^O, $^V, and $] arguments are replaced with constant terms like ``linux'', v5.16.1, and 5.016001, respectively.


Since regexp matching is not subject to constant folding, expressions like "$^O =~ /win32/i" will not be reduced.


Written by Alexey Tourbin <[email protected]>.


Copyright (c) 2012 Alexey Tourbin

This is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version.