Memory and References

Memory Model

• All objects may be allocated on the heap, managed by the GC.
• The compiler may perform escape analysis and keep data on the stack when safe.
• Users do not control allocation explicitly in v0.1.

Example:

string make() {
    let s = "hello";
    return s; // allocation strategy is compiler/runtime choice
}

Garbage Collector (v0.1)

• GC behavior is an implementation detail and is not observable from the language.
• The runtime uses a precise GC (details may change without affecting semantics).

References

• ref T denotes an explicit, read-only reference.
• out T denotes an explicit, write-only output reference (callee must assign).
• A reference cannot outlive the object it points to.
• ref mut T is not planned; ref and out are the explicit forms.

Ref/Out parameters

i32 len(ref string s) { return s.len(); }

Result<(), string> parse_port(out i32 port) {
    port = 8080;
    return Ok(());
}

Example usage:

i32 mut port = 0;
parse_port(out port)?;

Example

i32 len(ref string s) {
    return s.len();
}

Decisions

• ref/out are explicit and rely on GC/runtime safety (no borrow checking).
• Stack allocation may become observable via diagnostics, but this is a later feature.
• GC pacing and thresholds are implementation details and not part of v0.1.