# System Description: Twelf - A Meta-Logical Framework for Deductive Systems

@inproceedings{Pfenning1999SystemDT, title={System Description: Twelf - A Meta-Logical Framework for Deductive Systems}, author={F. Pfenning and C. Sch{\"u}rmann}, booktitle={CADE}, year={1999} }

Twelf is a meta-logical framework for the specification, implementation, and meta-theory of deductive systems from the theory of programming languages and logics. It relies on the LF type theory and the judgments-as-types methodology for specification [HHP93], a constraint logic programming interpreter for implementation [Pfe91], and the meta-logic M2 for reasoning about object languages encoded in LF [SP98]. It is a significant extension and complete reimplementation of the Elf system [Pfe94… Expand

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