NAME¶
B::ConstOptree - Optree constant folding for $^O, $^V, and $]
SYNOPSIS¶
$ perl -MO=ConstOptree -MO=Deparse} -e \
'require ($^O eq "MSWin32" ? "Win32.pm" : "POSIX.pm")'
require 'POSIX.pm';
-e syntax OK
DESCRIPTION¶
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 $] arguments are replaced with
constant terms like "linux", v5.16.1, and 5.016001, respectively.
CAVEATS¶
Since regexp matching is not subject to constant folding, expressions like
"$^O =~ /win32/i" will not be reduced.
AUTHOR¶
Written by Alexey Tourbin <at@altlinux.org>.
COPYING¶
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.
