Composition (Form II) {R}←A∘gY

g may be any dyadic function.  A may be any array whose items are appropriate to function g.  Y may be any array whose items are appropriate to function g.

The derived function is equivalent to AgY.  The derived function need not return a result.

Examples

      2 2∘⍴ ¨ 'AB'
 AA  BB
 AA  BB
 
      SINE ← 1∘○
 
      SINE 10 20 30
¯0.5440211109 0.9129452507 ¯0.9880316241

The following example uses Composition Forms I and II to list functions in the workspace:

      ⎕NL 3
ADD
PLUS
 
      ⎕∘←∘⎕VR¨↓⎕NL 3
     ∇ ADD X
[1]    →LAB⍴⍨0≠⎕NC'SUM' ⋄ SUM←0
[2]   LAB:SUM←SUM++/X
     ∇
     ∇ R←A PLUS B
[1]    R←A+B
     ∇