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Comment by fanf2 | Hacker News Reader

There’s a fun old-school spelling for the logical AND and OR operators in languages that officially spell them ∧ or ∨ but need to be typed in ASCII: /\ and \/

I am having trouble finding real world examples right now, but it happens in languages like ALGOL and CPL (tho they predate ASCII)

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TLA+ is an example. What I really like about this notation is you can use alignment to indicate precedence:

  \/ /\ A
     /\ B
  \/ /\ C
     /\ D

Which represents (A & B) || (C & D). It helps quite a bit for parsing large formulas in your head. In TLA+ the individual expressions are usually much more complicated than a single variable.

Aha, occam is another example, but it uses AND and OR for logical expressions but \/ or /\ for bitwise, plus the exciting >< for xor! http://transputer.net/obooks/obooks.asp

XOR is just a Boolean "not equal to"; if I had to express that with > and <, I would crib from BASIC and use <>.

MiniZinc uses the \/, /\, ->, <-> as the logical connectives.

Coq uses this notation for (propositional) and and or.

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