soder@inmic.se (Hakan Soderstrom) (01/17/91)
A while ago I thought I had a problem with Icon exit codes under recent versions of SunOS. I wondered if anyone could verify that an Icon program always exits by calling the Unix 'exit' and promised to post a summary. The summary is that without net response I had to resolve the problem myself. Icon very carefully exits through a Unix 'exit'. The problem I had turned out to be a C program which piped its output into the Icon program and exited by just flowing out of 'main'... I would like to remove any stain of suspicion against Icon that my previous posting might have caused among readers. The project I am involved in has developed an object-oriented database management system. In particular its DDL and DML compilers include 17.000 lines of Icon code and run on several major brands of Unix workstations. So far, we have never found a bug in Icon. (For the sake of portability we have avoided co-expressions, however.) Even more remarkable is that among all the complaints we have had about our system few, if any, have complained about the execution speed of the compilers. Our implementation technique is to implement lexer and parser as a C program, using lex and yacc. An Icon program reads the resulting parse tree and does all the semantic processing. -- ---------------------------------------------------- Hakan Soderstrom Phone: +46 (8) 752 1138 NMP-CAD Fax: +46 (8) 750 8056 P.O. Box 1193 E-mail: soder@nmpcad.se S-164 22 Kista, Sweden