Combinatory logic

:This article is about a topic in mathematical logic and theoretical computer science, and is not to be confused with combinatorial logic, a topic in electronics.

(S (K (S I)) K) (by η-reduction)

This combinator is equivalent to the earlier, longer one:

~ ~ ~ ~ ~ ~ ~ ~ ~ ~

(S (K (S I)) K x y)

~ ~ ~ ~ ~ ~ ~ ~ ~ ~