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I have a dumb question.

This code works well (THANKS Roy!) when looking for DNA string matches within a genome sequence but not when the * is changed to {50,100}

e.g.
/CCGG # Match starting at DNA sequence CCGG ( (?: (?!CCGG) # make sure we're not finding duplicates mid-stream . # accept any character )*? # any number of times BUT not greedily <==== ) AATT # and ending at AATT /x;

versus

/CCGG ( (?: (?!CCGG) . ){50,100}? # <==== ) AATT # and ending at AATT /x;

This latter one does not have dupes of CCGG but does have dupes of AATT. The previous snippet has no dupes of either CCGG or AATT.

A follow-up: The following code snippet fixes my problem, and I have NO idea why! I tried it out of desperation

/CCGG ( (?: (?!AATT|CCGG) # <============= . # ){50,100}? # Here the "?" is not required but I'm anal ) # AATT # /x;

In reply to Re^4: Using Look-ahead and Look-behind by JohnN
in thread Using Look-ahead and Look-behind by Roy Johnson

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