Abstract: Checking of user's commands in METHEDAS is the main subject in this paper.On basis of the syntactic structures of user's commands, the checking on following items:
1. command keywords and formats
2. parameter keywords, formats and their data types
3. rules of jointing commands with parameters
is completed by means of a code conversion module and a syntax parsing module, which compose an interpreter.
This interpreter, constructed within the FORTRAN-4 framework, is very successful in its simplicity, usefulness, and ability of simulating the string processing function, possessed by FORTRAN-77.