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store_contains(+StoreHandle, ++Key)
Check for an entry in a store object
- StoreHandle
- A store handle or store name
- Key
- A ground term
Description
	This checks whether a given store object contains an entry for a
	given key.  If so, the predicate succeeds, otherwise it fails.
	The key can be arbitrarily complex, but must be a ground term.
	The complexity of this  operation is linear in the size
	of the key, since the key needs to be compared. For indexing purposes,
	a hash value is computed from the key, and the full depth of the key
	is taken into account.
	Note: If StoreHandle is not a handle, then it must be an atom or a
	compound term, and the store is identified by this term's toplevel
	functor together with the context module.
    
Modes and Determinism
- store_contains(+, ++) is semidet
Modules
This predicate is sensitive to its module context (tool predicate, see @/2).
Fail Conditions
The store does not contain an entry for Key
Exceptions
- (4) instantiation fault 
- StoreHandle is uninstantiated
- (4) instantiation fault 
- Key is not ground
- (5) type error 
- StoreHandle is neither atom nor compound term nor store handle
- (45) named object does not exist 
- StoreHandle is not the name of a store
Examples
    ?- store_create(Handle),
       store_set(Handle, tom, 12345),
       store_contains(Handle, tom).
    Yes (0.00s cpu)
    ?- store_create(Handle),
       store_set(Handle, tom, 12345),
       store_contains(Handle, harry).
    No (0.00s cpu)
    
See Also
store / 1, store_create / 1, store_count / 2, store_get / 3, store_inc / 2, store_insert / 3, store_remove / 3, store_test_and_set / 4, store_update / 4