Hello Monks, I can't get a backreference to work properly. It is being replaced by my script as "$1" rather than the capturing group I want to be substituted instead. What (boneheaded no doubt) thing am I doing wrong? regex.txt contains the line: 
([A-Za-z])\.[A-Za-z],$1

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my $file = "regex.txt";
open FILE, "<", $file or die "Can't open $file: $!\n";
    while(my $regex=<FILE>){
        my @rex = split(/,/,$regex);
        chomp($rex[0]); # $rex[0] is set to "([A-Za-z])\.[A-Za-z]" 
        chomp($rex[1]); # $rex[1] is set to "$1" <--not sure how to ge
+t ([A-Za-z])group from $rex[0] to be set here.
        $rrow_test =~ s/$rex[0]/$rex[1]/ig;
    } # END while(my $regex=<FILE>)
close FILE;

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If I replace $1 in regex.txt with \1, I get the error: 
Reference to nonexistent group in regex; marked by <-- HERE in m/\1 <-
+- HERE / at C:\utilities\regexTester.pl line 105, <FILE> line 2.

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Thanks.

In reply to backreference replaced as literal or just fails by brwarn

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