Anchors

/^ab/

• Attempt to match ^ fails unless cursor is before the first character of the string

• But also, the start node is altered so that the engine can only start at the beginning of the string

• grab

             START             |g r a b 
             ^                 |g r a b              Yes!
             ab                |g r a b              Nope

• Match fails.

• More about optimizations later

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Copyright © 2002 M. J. Dominus