NB: More recent documentation for Dyalog APL is available at https://docs.dyalog.com/20.0/.

Dyadic Left Arrow means

Naming

    V ← 5 6 7
    (i(j k)) ← 4(5 6)
    sum ← +⌿
    product ← {×/⍵}
    inverse ← ⍣¯1

Operator Left Arrow means

Modified Assignment

    V +← 1
    V[2] ← 0
    (⊃V) ← 2

Language Elements