1. A method of matching a string of symbols to a regular expression pattern, said regular expression pattern comprising a first constant, a second constant, and a first operator, said first operator occurring before said first constant in said regular expression pattern, comprising: matching said first constant using a deterministic finite automaton (DFA); and, in response to matching said first constant, matching said first operator by determining if a member of a complement of a symbol set defined by said first operator occurred in said string of symbols between a starting position of said first operator in said string of symbols and an ending position of said first operator in said string of symbols.