Dear Monks,

So in attempting to become a totally awesome regexer, I have run into a problem that I am hoping you can assist me with.

Specifically I have the following problem, I have text patterns and strings that I want to count the patterns in, but I want to allow for overlapping patterns in the string. I have hunted around these forums and found some good advice, but I have an additional problem. Here is what I can get: 

my $first_counter = 0;
my $second_counter = 0;

my $sequence = "GGGGGGGAGAAAAAAAAAAAAAAAGAAGGA";

# This is what I initially did, but did not get the right answer

$first_counter++ while $sequence =~/AAAAA/g; #Here I get 3

# Because I want to count the overlapping AAAAA in the sequence I hunt
+ed around and found this solution

$sequence =~ /AAAAA(?{$second_counter++})(?!)/; # This gives the right
+ answer of 11

print "First counter: $first_counter\n";
print "Second counter: $second_counter\n";

[download]
Now what I really want to do is that instead of putting in the pattern in the search, I would like to pass it as a variable, i.e. something like: 
my @real_count = (0,0,0,0);
my $sequence = "GGGGGGGAGAAAAAAAAAAAAAAAGAAGGA";
my @pattern;
$pattern[0] = "AAAAA";
$pattern[1] = "GGGGG";
$pattern[2] = "GGAGA";
$pattern[3] = "GAAGG";

for (my $i=0; $i <= 3; $i++) {
    $sequence =~ /$pattern[$i](?{$real_count[$i]++})(?!)/;
}

foreach (@real_count) {
    print "$_\n";
}

[download]
When I run the above I get the following error message (which I admit I do not understand):

"Eval-group not allowed at runtime, use re 'eval' in regex m/AAAAA(?{$real_count$i++})(?!)/ at E:\Bioreka\Test\multimatch.pl line 13."

Can anyone help point me to how to address this error? I would appreciate it. Thanks in advance.

In reply to Regex KungFu help needed by drblove27

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