5. The method of claim 3 , wherein said congruence of said suffix is established by determining that likewise positioned characters in said suffix and said respective portion of said data stream belong to a same character class from among said predefined set of character classes.
3. The method of claim 1 further comprising: determining a value of said state variable at a target position, said target position corresponding to a last location index of an end character of a last string segment within said complex string; ascertaining occurrence of said complex string within said data stream terminating at a position index equal to said current simple-matching position plus a length of said suffix subject to: said state variable containing a logical “1” at said target position; and congruence of said suffix with a respective portion of said data stream succeeding said current simple-matching position.