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Predicate make_varnames/5
 make_varnames(+ReadClause, +DecompiledClause, +Offsets, +Names, -Term) is det[private]
Create a Term varnames(...) where each argument contains the name of the variable at that offset. If the read Clause is a DCG rule, name the two last arguments <DCG_list> and <DCG_tail>

This predicate calles the multifile predicate make_varnames_hook/5 with the same arguments to allow for user extensions. Extending this predicate is needed if a compiler adds additional arguments to the clause head that must be made visible in the GUI tracer.

Arguments:
Offsets- List of Offset=Var
Names- List of Name=Var