tree ebee9e19a7b9f50a3b0c99653454100b387ede40
parent 4c084aa1e09afd1127ebbcec63a5cfd6a2eb3b78
author Z <zhqhku@gmail.com> 1440673457 -0500
committer Z <zhqhku@gmail.com> 1440673457 -0500

added documentation for new lookahead