The generation scheme discussed, produces interactive transducers in the form of Ada programs, with an underlying parser that is of type ELL(1). The emphasis is on error recovery in interactive parsers. A generation scheme is proposed containing powerful error-recovery generation capabilities. The interaction between syntactic and semantic error recovery is also discussed. The generation scheme has been implemented as part of the MIRA transducer writing system. With MIRA, a number of industrial case studies have been worked out, from which considerable feedback has been obtained to test and improve the adopted error-recovery strategy. One of the case studies worked out with MIRA consists of the design and implementation of an interactive software package called ABACUS. A subset called MINI-ABACUS is used as an illustration of the error-recovery principles discussed throughout this work.>

Abstract This paper describes an exception detection and exception handling method for constructive algebraic specifications. A notation that supports exception handling is introduced. First, a safety function is provided for every sort. This function characterizes each object as being safe or unsafe. Secondly, axioms may contain markers that indicate when they are applicable. The proposed notation is a trade‐off between readability and capability to handle a large class of exceptional situations. The description of exception handling promotes a two‐step design method for constructive algebraic specifications. In a first step the specification is given with exception detection only; in a second step exception handling is superimposed.