A preprocessor is a program which translates statements written in a language X into FORTRAN. In our case X is called SPARKS. Such a program is normally called a compiler so why give it the special name preprocessor? A preprocessor is distinguished from a compiler in the following way: the source and target language have many statements in common.
Such a translator has many advantages. Most importantly it preserves a close connection with FORTRAN. Despite FORTRAN's many negative attributes, it has several practical pluses: 1) it is almost always available and compilers are often good, 2) there is a language standard which allows a degree of portability not obtainable with other languages, 3) there are extensive subroutine libraries, and 4) there is a large labor force familiar with it. These reasons give FORTRAN a strong hold in the industrial marketplace. A structured FORTRAN translator preserves these virtues while it augments the language with improved syntactical constructs and other useful features.
Another consideration is that at many installations a nicely structured language is unavailable. In this event a translator provides a simple means for supplementing an existing FORTRAN capability. The translator to be described here can be obtained by writing to the address given at the end of this appendix.
