I am in the midst<sp?> of reading apocalypse5 and have run across a listing if expresions based on "?". Some are obvious, some not so much. Could one or more of the local Monks possibly take a moment to do a rundown of what exactly they all mean...and maybe in what situations you might use them? Thanks, John

Below are the expressions: 

    (??{...})
    (?{...})
    (?#...)
    (?:...)
    (?i:...)
    (?=...)
    (?!...)
    (?<=...)
    (?<!...)
    (?>...)
    (?(...)...|...)

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In reply to ? expresions from Apocalypse5 by dimes

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