So you've got multiple possible strings, and some of them might be substrings of others of them? If you combine them into one alternation, longest first, you should be ok: 
my $super_regex = join '|', sort {length $b <=> length $a} map quoteme
+ta($_), @list;
$var_val =~ s/($super_regex)/$prefix$1$suffix/g;

[download]
Regexp::Optimizer might be of use if @list is long.

Update: added quotemeta as per ikegami's note.

Caution: Contents may have been coded under pressure.

In reply to Re: Regex help by Roy Johnson
in thread Regex help by snacktime

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