Why settle for three states when you can have a range of confidence? Read up on fuzzy sets.

There are already some calls in Perl (and other languages like C) that return yes/no/error values. This means that if you're handling errors correctly you're already handling three-state logic.

The language itself need not support three-state variables in order for you to write a program with three-state logic. It certainly could help. In the meantime, though, there are positive/negative/zero and less/equal/more available. Integers or even floating point numbers (0 to 1 instead of 0 to infinity) are very useful as truth values or condition markers in some situations.

What you're likely missing isn't a way to represent more than two states in a variable, since lots of data structures and even simple scalars can give you that. What's really handy is an N-way control flow which given/when can provide.

In reply to Re: Will Perl6 be able to do this kind of logic? by mr_mischief
in thread Will Perl6 be able to do this kind of logic? by zentara

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