
update(+Tree0, ++Key, ?Value, -Tree)

   Update the value corresponding to a key in a tree.

Arguments
   Tree0               A 2-3-4 tree
   Key                 A key to update
   Value               The value corresponding to Key
   Tree                The tree after updating

Type
   library(m_tree234)

Description
	
	If the key Key already exists in the tree Tree0, then this predicate
	updates the corresponding value to be Value.  The resulting tree is
	Tree.
	
	
	This predicate should only be called with trees created by other
	predicates from the tree234 module.
	
	

Fail Conditions
   Fails if Key does not appear in Tree0.

Resatisfiable
   no

See Also
   insert / 4, set / 4
