Thanks! I guess that explains it. I'm not sure why ((?:^(?:aaa|bbb|ccc))|(?:ddd|eee|ccc)) can be optimised but not (?:^aaa|ddd), but it is what it is.

In reply to Re^2: Alternations and anchors (trie optimization) by Chuma
in thread Alternations and anchors by Chuma

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