Module iter 

Lazy iterator protocol for the Harn VM.

VmIter is the backing enum for VmValue::Iter. It’s a single-pass, fused iterator; once next returns None the variant is replaced with Exhausted. Step (a) only introduces source variants (Vec, Dict, Chars, Gen, Chan, Exhausted) and wires them into the for-loop driver. Combinator variants (Map, Filter, Take, …) and sink builtins land in later steps per the plan.

Enums

VmIter

Backing enum for VmValue::Iter. See module docs.

Functions

drain

Fully consume an iter handle into a Vec of values.

iter_from_value

Convenience: wrap a source value into a VmValue::Iter. Used by the iter() builtin and by combinator/sink implementations in later steps.

next_handle

Advance a handle without holding a RefCell borrow across the await.