In this case, though, I was trying to make certain that
the non-backslash characters preceeding the variable did
not get included in the match result.
As you pointed out below, though, the look-behind assertion
was what I had in mind, but for some reason I was lead to
believe that they didn't work properly in some cases, but
those cases seem to be pretty specific, or related to
some earlier version of perl.
had provided
a demonstration on the perils of negative lookback, but
I can't find it.