A.46 library(rbtrees): Red black trees
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Availability::- use_module(library(rbtrees)).(can be autoloaded)
Source[semidet]rb_apply(+Tree, +Key, :G, -NewTree)
If the value associated with key Key is Val0 in Tree, and if call(G,Val0,ValF) holds, then NewTree differs from Tree only in that Key is associated with value ValF in tree NewTree. Fails if it cannot find Key in Tree, or if call(G,Val0,ValF) is not satisfiable.