In old age, things of the mind ,left unused, will just slip away.
I know there is a style of variable usage that allows the juxtaposition of the variable and a literal character that could be part of the name: 
 my $v1 = 'A';
 my $v2 = 'B'
 my answer is "_$v1_$v2_";

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This will not compile, as I want; a string of the 2 variables surrounded by underscores "_A_B_".
I do not want the underscores as separate strings with concatenates between.
I think I remember something like "_{$v1}_" and I have no idea how to phrase a net search.

It is always better to have seen your target for yourself, rather than depend upon someone else's description.

In reply to A simple question that can't be asked by Wiggins

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