Struct Raised 

pub struct Raised<'id> { /* private fields */ }

Proof that an exception is pending on a CallEnv.

A term-less typestate token: it can only be produced by an operation that raises or detects a pending exception, so holding one means the env is in the pending-exception state in which no further env operation is valid. Propagate it straight out of the NIF with ?; the generated wrapper returns the non-value word and the BEAM raises the pending exception. (No term is kept — detection via has_pending_exception yields no reason term, and the returned word is ignored once an exception is pending.)