  Recent years have seen an increasing need of high-level specification
languages and tools generating code from specifications. In this paper, we
introduce a specification language, {\splname}, which is tailored to the
writing of syntactic theories of language semantics. More specifically, the
language supports specifying primitive notions such as dynamic constraints,
contexts, axioms, and inference rules. We also introduce a system which
generates interpreters from {\splname} specifications. A prototype system is
implemented and has been tested on a number of examples, including a syntactic
theory for Verilog.
