1ConstOptree(3) User Contributed Perl Documentation ConstOptree(3)
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6 B::ConstOptree - Optree constant folding for $^O, $^V, and $]
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9 $ perl -MO=ConstOptree -MO=Deparse} -e \
10 'require ($^O eq "MSWin32" ? "Win32.pm" : "POSIX.pm")'
11 require 'POSIX.pm';
12 -e syntax OK
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15 This module propagates constant folding for $^O, $^V, and $] variables
16 by installing custom PL_check handlers for numeric and string
17 comparison opcodes. In the handlers, references to $^O, $^V, and $]
18 arguments are replaced with constant terms like "linux", v5.16.1, and
19 5.016001, respectively.
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22 Since regexp matching is not subject to constant folding, expressions
23 like "$^O =~ /win32/i" will not be reduced.
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26 Written by Alexey Tourbin <at@altlinux.org>.
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29 Copyright (c) 2012 Alexey Tourbin
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31 This is free software; you can redistribute it and/or modify it under
32 the terms of the GNU General Public License as published by the Free
33 Software Foundation; either version 2 of the License, or (at your
34 option) any later version.
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38perl v5.38.0 2023-08-01 ConstOptree(3)