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recorda(+Key, ?Value, -DBRef)

Records the term Value before all other entries for key Key in the record database.
Key
An atom, compound term, or handle.
Value
An arbitrary term.
DBRef
A variable.

Description

Used to record an arbitrary term Value at the beginning of the record database entry associated with the key Key. Unlike recorda/2, this predicate delivers a so-called database reference in DBRef which is a unique handle for the record database entry that is created. In the case of compound terms, all keys of the same name and arity are treated as equal.

If backtracking occurs through the call of recorda/3 the associated Value is not removed from the record database.

Modes and Determinism

Modules

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

Exceptions

(4) instantiation fault
Key is not instantiated.
(5) type error
Key is neither atom, compound term, nor record handle.
(5) type error
DBRef neither a variable nor a database reference.

Examples

   Success:
    [eclipse]: recorda(whiskey,jameson,Ref1),
             recorda(whiskey,bushmills,Ref2).
    Ref1 = $&(dbref,"370h7n")
    Ref2 = $&(dbref,"370h87")
    yes.
Error:
    recorda(Key, anything, Ref).          (Error 4)
    recorda("key",anything, Ref).         (Error 5)
    recorda(key,anything, 99).            (Error 5)

See Also

recordz / 3, recorded / 3, is_handle / 1, erase / 1, referenced_record / 2