Ratatosk
An SLR parser generator written in Gofer (a Haskell variant) by Torben AEgidius Mogensen
Even though the sematic value of a production is a function of the attributes of its right-hand side (and thus apparently purely synthesised), inherited attributes are easily simulated by using higher-order functions.
(ftp://ftp.diku.dk/pub/diku/dists/Ratatosk.tar.Z).