A debugger and assertion checker for the Awk programming language

The paper describes the design and implementation of our Awk User Interface (AUI). AUI is a graphical programming environment for editing, running, testing and debugging of Awk programs. The AUI environment supports tracing of Awk programs, setting of breakpoints, and inspection of variable values. An assertion language to describe relationships between input and output of Awk programs is provided. Assertions can be checked after the program has run, and if violated, informative and readable messages can be generated. The assertions and debugging rules for the Awk program are written in a separate text file. Assertions are useful not only for testing and debugging but can be considered as a tool for formal program specification and documentation.