As you can see in the first example, ":" is part of the matched string, and you're excluding it in the second. That's why it only matchs "d" on:

triple hybrid: dehydrofolate
            ^--Here

[download]
And substitutes the full "d: d" by only d. Try adding ":" to your character class (s/([()\w\s:-]+): \1/$1/).

In reply to Re: Understanding regex by deibyz
in thread Understanding regex by Hena

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