stchang/parsack — pull request #17 by greghendershott (2013-11-07 19:19:39+00:00)
Title: lookAhead returns parse result, but still consumes no input.

Note: This required updating `check-empty-parsing` in test-utils.rkt to
check for a result, just like `check-parsing`. For parsers like $eof
the result is "".