Scala - Prefix Unary Operators

scala logic notation unary-operator
wen picture wen · Sep 6, 2010 · Viewed 12k times · Source

I've recently given Scala a second chance, and started with the project I always implement (in functional or pseudo-functional languages): an automated reasoner for propositional logic (and later predicate logic).

Now, I've tried to get the notation of propositional logic in the language itself as pretty as possible, and I've gotten this far - with an implicit conversion (String -> Atom):

("A" and "B") implies "C"

The functions "and" and "implies" (and "or" and "equivalent") are simple methods that call the relevant case class constructor. However, when implementing "not", I get stuck with either of the two following notations:

("A" and "B").not
Not("A" and "B")

Is there a way to trick Scala into accepting the desired:

not("A" and "B")

Preferrably without renaming the class "Not" to "not", because I might like to call it "¬" or something else, in th future.

Answer

Paul Ruane picture Paul Ruane · Sep 6, 2010

I noticed on this answer to another question that it appears that one can prefix the operator name with unary_ to achive what you are trying to do. (See unary_!.)

Edit: this article confirms the syntax.

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