Middle Dot (·)

·: Nothing

→full documentation

Indicates no value. If a left argument is Nothing, the function is called with no left argument, and if the right is Nothing, it's not called and "returns" Nothing.

    ·  "abc"  # Reverse instead of Rotate

In Trains

→full documentation

Nothing can serve as a left argument in a train to string together multiple monadic functions.

    (-+-) 5

    (-·+-) 5


→full documentation

For pattern matching in assignment or a block header, Nothing indicates an unused value.

    F  {𝕊 a·b: ab}

    F 123
⟨ 1 3 ⟩