For some reason, it's hard to visualize the precedence in a regex; maybe it's the lack of whitespace (unless you use //x). Anyway, your attempt has a precedence problem. It's parsed as a match of either /SW=?/ or /:?\s*(..../. Enclose the | and its choices in (?:   ) like so: /SW(?:=?|:?)\s*.../ though you don't need ? on both alternatives. In fact, you could say (?:=|:|) (using an empty alternative) or (?:=?|:) or (?:=|:)? or [=:]?.

By "ignore the word 'SWITCH'" do you mean allow SWITCH or SW interchangably? If so, replace SW with SW(?:ITCH)?.

In reply to Re: combining RegEx by ysth
in thread combining RegEx by Anonymous Monk

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