# threaded_engine_next_reified/2

## Description

    threaded_engine_next_reified(Engine, Answer)

Retrieves the next reified answer from an engine. This predicate always succeeds and blocks until an answer becomes available. Answers are returned using the terms `the(Answer)`, `no`, and `exception(Error)`.

## Modes and number of proofs

    threaded_engine_next_reified(@nonvar, ?nonvar) - one

## Errors

Engine is a variable:
`instantiation_error`
Engine is neither a variable nor the name of an existing engine:
`existence_error(engine, Engine)`

## Examples

    % get the next answer from the worker_1 engine:
    | ?- threaded_engine_next_reified(worker_1, Answer).

See also

threaded_engine_create/3, threaded_engine_next/2, threaded_engine_yield/1