tree 7ef22e646a84e5d1d052a8dada0d24d16bb689d0
parent fe8235a9799c0e6b0d49d1d46431e232ab26324d
author Shawn O. Pearce <sop@google.com> 1308329689 -0700
committer Shawn O. Pearce <sop@google.com> 1308329689 -0700

Make Prolog.copyHash an IdentityHashMap

The map is used only for VariableTerms that have not yet
been resolved to a value. In this case the only equality
that makes sense is identity equality. The identity map
is faster as it always avoids the virtual hashCode()
and equals() methods on the keys.