A combinator is a function or operator that only refers to its arguments and operands without modifying them in any way. Symbol APL expression Bird(1) TinyAPL Diagram
I
\mathrm I
I y Identity ⊣/⊢
K
\mathrm K
K x Kestrel ⊣
κ
\kappa
κ y Kite ⊢
W
\mathrm W
W y F y Warbler ⍨
C
\mathrm C
C y F x Cardinal ⍨
B
\mathrm B
B F (G y) Bluebird ∘/⍤/⍥
Q
\mathrm Q
Q G (F y) Queer ⍛
B 1
{\mathrm B}_1
B1 F (x G y) Blackbird ⍤
Ψ
\Psi
Ψ (G x) F (G y) Psi ⍥
S
\mathrm S
S y F (G y) Sta