MAX-UTREE-DEPTH : FLAGMAX-UTREE-DEPTH is a flag or parameter.
If non-NIL, maximum depth to which unification tree is to be
generated. Used only in UN88 procedures. This variable is incremented
during mating-search to allow unification tree to grow to
greater depth as the search progresses. The unification tree
is, however, never searched or generated to a depth greater than
MAX-SEARCH-DEPTH provided it is non NIL and a positive integer. One can
also consider this variable to be the initial value to which unification
trees are generated during mating-search.
MAX-UTREE-DEPTH takes values of type NULL-OR-POSINTEGER.
It belongs to subjects IMPORTANT UNIFICATION .
Its default value is 5
Its current value is 5.
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