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`library(rem)`

This library module maintains equivalence classes using Rem’s algorithm. Exported predicates:

`rem_create(`

`+Size`,`-REM`)-
creates an equivalence representation function

`REM`which maps each of the nodes`1..Size`to itself. `rem_head(`

`?Node`,`+REM`,`-Head`)-
is true when

`Head`is the representative of the equivalence class that`Node`belongs to in the given`REM`. `rem_equivalent(`

`?Node1`,`?Node2`,`+REM`)-
is true when

`Node1`and`Node2`belong to the same equivalence class in the given`REM`. `rem_add_link(`

`?Node1`,`?Node2`,`+OldREM`,`-NewREM`)-
is true when adding the equivalence

`Node1===Node2`to the partition represented by`OldREM`yields a partition which is represented by`NewREM`. If`Node1`or`Node2`is uninstantiated, it will backtrack over all the nodes. It’s not clear how useful this is.

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