rb_update/4

Availability::- use_module(library(rbtrees)).(can be autoloaded)

[semidet]rb_update(+Tree, +Key, ?NewVal, -NewTree)

Tree NewTree is tree Tree, but with value for Key associated with NewVal. Fails if Key is not in Tree (using (==)/2). This predicate may fail or give unexpected results if Key is not sufficiently instantiated.

See also: rb_in/3 for backtracking over keys.