Debugging framework for attribute grammars

Abstract

Attribute grammars provide a formal means to specify the semantics of context free grammars. In this work, we propose a method to debug attribute grammars by applying algorithmic debugging to the paradigm of attribute grammars. The technique of algorithmic debugging uses the data flow of a program to debug it rather than stepping through its source code thereby making it suitable for declarative platforms like attribute grammars. In a debugging session, dependencies between attributes are obtained and used to construct an execution tree which is then traversed by the debugger based on interactions with the user. The debugger asks the user questions about the validity of a node in the execution tree and about the search space to be explored. Based on the user's response to the questions the debugger identifies the incorrect equation in a production definition. Further, we also propose a means to improve the debugging process by using a guided heuristic based mechanism which helps in reducing the number of questions to the user regarding the search space to be explored next.