Alan M. Davis

CAPS is a highly interactive diagnostic compiler/interpreter that allows beginning programmers to prepare, debug, and execute fairly simple programs at a graphics display terminal. Complete syntax checking and most semantic analysis is performed as the program is entered and as it is subsequently edited. Analysis is performed character by character. The most remarkable feature of CAPS is its ability to automatically diagnose errors both at compile time and at run time. Errors are not automatically corrected. Instead, CAPS interacts with the student to help him find the cause of his error. Most components of CAPS are table driven, both to reduce the space needed for implementation and to increase the flexibility of the multilingual system. Over 500 students have used CAPS to learn Fortran, PL/I, or Cobol in conjunction with a computer assisted course on introductory computer science.