13 lines
671 B
Plaintext
13 lines
671 B
Plaintext
Perl's built-in logical operators, C<and>, C<or>, C<xor> and C<not>
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support 2-value logic. This means that they always produce a result
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which is either true or false. In fact perl sometimes returns 0 and
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sometimes returns undef for false depending on the operator and the
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order of the arguments. For "true" Perl generally returns the first
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value that evaluated to true which turns out to be extremely useful
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in practice. Given the choice Perl's built-in logical operators are
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to be preferred -- but when you really want pure 2-degree logic or
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3-degree logic or multi-degree logic they are available through
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this module
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WWW: http://search.cpan.org/search?dist=Math-Logic
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