Coyote Point Systems Equalizer GX Series, Administration Manual

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How to Use Regular Expressions
Matching in Regular Expressions
If a real expression could match more than one substring of a given string, the real expression
matches the one starting earliest in the string. If the real expression could match more than one
substring starting at that point, it matches the longest. Subexpressions also match the longest
possible substrings, subject to the constraint that the whole match be as long as possible, with
subexpressions starting earlier in the real expression taking priority over ones starting later. Note
that higher-level subexpressions thus take priority over their lower-level component
subexpressions.
Match lengths are measured in characters, not collating elements. A null string is considered
longer than no match at all. For example, 'bb*' matches the three middle characters of 'abbbc', '
(wee|week)(knights|nights)' matches all ten characters of 'weeknights', when '(.*).*' is matched
against 'abc' the parenthesized subexpression matches all three characters, and when '(a*)*' is
matched against 'bc' both the whole real expression and the parenthesized subexpression match
the null string.
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