APL Dialect Compatibility — Dyalog APL, GNU APL & mAPL

APL Run defaults to Dyalog-compatible APL (⎕IO←1) enhanced with mAPL extensions, and supports switching to strict GNU APL compatibility mode via ⎕DIALECT←'gnu'.

Supported Feature Categories

• Core Primitives: + - × ÷ * ⍟ | ⌈ ⌊ ! ○ ⍴ ⍉ , ⍪ ⌽ ⊖ ↑ ↓ ⊂ ⊃ ⊆ ⍳ ⍸ ∊ ⍷ ∪ ∩ ⍋ ⍒ ≡ ≢ ⊥ ⊤ ⌹ ?
• Operators: / \ ⌿ ⍀ ¨ ⍨ ⍣ ∘ . plus Dyalog operators Rank (⍤), Over (⍥), At (@), Key (⌸), Stencil (⌺), Variant (⍠), and mAPL Pipeline (▷).
• Functions & Control Flow: Dfns ({⍺ ⍵}), guards, tacit 2-trains and 3-trains (forks), tradfns (∇), and structured control blocks (:If :For :While :Repeat :Select).
• System Functions: ⎕IO ⎕TS ⎕UCS ⎕CT ⎕PP ⎕PW ⎕JSON ⎕CSV ⎕XML ⎕NS ⎕NC ⎕NL ⎕RENDER.