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recorded(+Key, ?Value)

Succeeds if the term Value has been recorded in the record database under the key Key.

Key: An atom or a compound term.
Value: An arbitrary term.

Description

Used to find all values associated with a key. Unifies Value with the first term that has been associated with Key. In the case of compound terms, all keys of the same name and arity are treated as equal. If Value is instantiated, the instantiated term is used as a filter to reduce the number of terms returned by the recorded database and unified with Value, thus improving the speed of retrieving the term.

Backtracking will unify Value with successive values associated with Key in the order in which they were recorded.

Modes and Determinism

recorded(+, -) is nondet
recorded(+, +) is nondet

Modules

This predicate is sensitive to its module context (tool predicate, see @/2).

Fail Conditions

Fails if nothing is recorded under the key Key

Exceptions

(4) instantiation fault: Key is not instantiated.
(5) type error: Key is neither atom, compound term, nor record handle.

Examples

   Success:
   [eclipse]: record(beer,paulaner),
   >        record(beer,lowenbrau),
   >        record(beer,spaten),
   >        recorded(beer,Value).
   Value = paulaner     More? (;)
   Value = lowenbrau     More? (;)
   Value = spaten     More? (;)
   no (more) solution.
   Fail:
   erase_all(beer),recorded(beer,guiness).
   Error:
   recorded(Beer,Value).                (Error 4)
   recorded("beer",Value).              (Error 5)
   recorded(1,Value).                   (Error 5)