10 lines
619 B
Text
10 lines
619 B
Text
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
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and sometimes returns undef for false depending on the operator
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and the order of the arguments. For "true" Perl generally returns
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the first value that evaluated to true which turns out to be
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extremely useful in practice. Given the choice Perl's built-in
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logical operators are to be preferred -- but when you really want
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pure 2-degree logic or 3-degree logic or multi-degree logic they
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are available through this module
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