摘要:Many computer science applications concern properties that are true for a restricted class of models. In this paper, a couple of constructor-based institutions are presented. These institutions are defined on top of some base institutions, roughly speaking, by enhancing the syntax with constructor symbols and restricting the semantics to models with elements that are reachable by constructors. The proof rules for the constructor-based Horn logics, formalized asinstitutions, are defined in this paper, and a proof of completeness is provided in the abstract framework of institutions..