• MatchLocalNames is an option for Trace and related functions which specifies whether symbols such as x should match symbols with local names of the form x$nnn.
• The default setting is MatchLocalNames -> True.
• With the default setting, Trace[expr, x = rhs] will show assignments to local variables whose names are of the form x$nnn.
• Trace[expr, x = rhs, MatchLocalNames->False] shows assignments only for the global symbol x.
• New in Version 2.