
erase(+DBRef)

   Succeeds if the database reference DBRef designates a term recorded in the
indexed database and this term is successfully erased.



Arguments
   DBRef               A database reference.

Type
   Recorded Database

Description
   The database reference DBRef must refer to a term that has been recorded
   in the indexed database.  Database references can be obtained from the
   predicates recorda/3, recordz/3 and recorded/3.  If the referenced term
   has already been erased, erase/1 fails.  Backtracking through calls of
   erase/1 does not undo an erasure.  Note that database references are not
   integers.




Modes and Determinism
   erase(+) is semidet

Fail Conditions
   Fails if DBRef refers to an already erased record

Exceptions
     4 --- DBRef is not instantiated.
     5 --- DBRef is not a database reference.

Examples
   
   Success:
   [eclipse]: recordz(whiskey, jameson, _),
   recordz(whiskey, glenfiddich, Ref),
   recordz(whiskey, dimple, _),
   erase(Ref).
   Ref = 98538
   yes.
   [eclipse]: recorded(whiskey, L, _).
   L = jameson     More? (;)
   L = dimple     More? (;)
   no (more) solution.
   Fail:
   [eclipse]: recorded(whiskey,_,R), !, erase(R), erase(R).
   no (more) solution.
   Error:
   erase(Var).                            (Error 4)
   erase(123).                            (Error 5)





See Also
   erase_all / 1, recorda / 3, recordz / 3, recorded / 3, referenced_record / 2
