built-in predicate
extends_protocol/2-3
Description
extends_protocol(Protocol, ParentProtocol)
extends_protocol(Protocol, ParentProtocol, Scope)
Enumerates, by backtracking, all pairs of protocols such that the first
one extends the second. The relation scope is represented by the atoms
public, protected, and private.
Modes and number of proofs
extends_protocol(?protocol_identifier, ?protocol_identifier) - zero_or_more
extends_protocol(?protocol_identifier, ?protocol_identifier, ?scope) - zero_or_more
Errors
Protocol is neither a variable nor a valid protocol identifier:type_error(protocol_identifier, Protocol)ParentProtocol is neither a variable nor a valid protocol identifier:type_error(protocol_identifier, ParentProtocol)Scope is neither a variable nor an atom:type_error(atom, Scope)Scope is an atom but an invalid entity scope:domain_error(scope, Scope)Examples
% enumerate the protocols extended by the listp protocol:
| ?- extends_protocol(listp, Protocol).
% enumerate protocols that privately extend the termp protocol:
| ?- extends_protocol(Protocol, termp, private).