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v0.14.0

== and != reject non-primitive operands instead of dispatching through Eq

Limitation​

Construction accepts ==/!= only when the operand type is numeric, boolean, String, char or Never. Any other type, including a struct that implements Eq, is rejected rather than dispatched to the Eq aspect. Reproduced against current develop:

struct P { x: i64 }
fun main() {
    let a := P { x = 1 };
    let b := P { x = 1 };
    assert(a == b);
}
[T0005] type error: equality comparison requires a primitive operand (numeric, boolean, String, or char), got `P`; `==` does not yet dispatch through the `Eq` aspect — use `.eq(..)` on a type that implements it

The guard deliberately rejects rather than peeling references, to avoid committing the language to referent-equality versus identity semantics.

Impact​

Visible to Metel programmers: user types must call .eq(..) explicitly. The source comment attributes the fix to metel-core#263, which is now about Copy rules for tuples and arrays; the reference is stale and the follow-up issue needs to be found or filed.

Affects​

Resolution​

None yet; needs a tracking issue (the cited #263 no longer matches).