Recently, many unification-based grammar formalisms (eg. LFG, HPSG) have been appeared in linguistics area. But it is difficult to implement them for lack of suitable programming languages or software tools.
In this thesis, a very high-level programming language FUL (Feature Unification Language) is designed and implemented to resolve the above problem. FUL has an extended unification and a powerful structure sharing. Implementations of two prototype parsers (LFG and HPSG parsers) using FUL had shown the power of FUL.