A pascal implementation of a display system for pascal programs

First year students of computing science at this university learn to program in the teaching language Pascal. using the department's computer. a Perkin-Elmer 3220. running under UNIX. version 7. Under this version of UNIX. we have a Pascal interpreter and a "pretty printer" called pxp which can be used to format Pascal programs and also to produce an execution profile. What we do not have is a Pascal debugging system. We have found ourselves spending an inordinately large amount of time helping our students to debug programs.