AST Compiler Execution Badges

Inspect how the APL Run compiler optimizes and executes every node of your APL program in the AST Viewer:

• ● Compiled — Dfn or sub-expression compiled to vector bytecode VM instructions.
• ♻ TCO (Tail Call Optimization) — Recursive self-call (∇) in tail position reuses stack frames in O(1) space.
• 🔥 Fused — Element-wise operator chain merged into a single-pass register loop with zero intermediate array allocations.
• ⚡ Specialized — Unboxed Real1D gradual-type VM fast path or pattern-inlined operator (e.g. {≢⍵}⌸).