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I disagree.

The problem is not in defining 'true' and 'false' constants other than ones predefined by the language. The real problem is using any such Boolean constants in (in)equality expressions.

One should never write anything like "== false" and one should rewrite any such code that one runs into (when practical). For one thing, it is needless complex, even redundant.

Yes, defining 'true' and 'false' constants exacerbates this problem and the problem is somewhat mitigated when a language has a first-class Boolean data type (that can't be made to hold other than the two special values) -- which also means that the language likely defines its own symbolic representations for those two special values.

But one can certainly sanely use 'true' and 'false' constants even in Perl. Just don't test for equality against Boolean values, especially against Boolean constants. And one should follow this practice even in languages where a real Boolean datatype mitigates the seriousness of such redundant constructs.

- tye

In reply to Re^3: Burned by precedence rules (== true) by tye
in thread Burned by precedence rules by vrk

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