Memory semantics

Norm specifies observable values and identity, not object layout or a memory-management algorithm. The concrete assignment rules are defined by value and identity semantics.

Observable behavior

• A value is logically independent after assignment, argument passing, and return.
• Class operations share object identity.
• class.copy() creates a new top-level object identity.
• Values compare structurally; classes compare by identity.
• Arguments and subexpressions are evaluated from left to right in source order.

Implementations may use eager copying, copy-on-write, structural sharing, and escape analysis. Optimizations must not change these behaviors.

Lifetime

Programs do not manually release ordinary values or class instances. Reachable objects must remain valid; external resources are managed through explicit scoped APIs. Ordinary programs are not required to recover reliably from out-of-memory or stack-overflow conditions.

Addressable locations, escape restrictions, and lexical lifetime for ref<T> are defined together in the reference rules.