Class Scope

Spawn a child frame whose lexical parent is this one.

Declare name in this frame, shadowing any ancestor binding. Param binding and explicit local declaration use this.

Resolve name walking outward from this frame. Returns the bound value or undefined when unbound anywhere in the chain. Note that a binding whose value is undefined (void) is indistinguishable from absence by this accessor — use has to disambiguate.

Recursive over the lexical chain (rather than a this-aliasing loop); chains are shallow — one frame per nesting level.

The lexical parent, or null for a root frame.

True iff name is bound in this frame or any ancestor.

Assign name. Writes to the nearest existing binding up the chain; if name is unbound everywhere, creates it in this frame. This is set name (...) semantics — assignment, not declaration.