gudeman@arizona.UUCP (04/08/87)
From: janssen@milano.UUCP Date: 3 Apr 87 18:47:15 GMT Can anyone provide names and addresses, or article citations, that I could contact or read for more information on ICON? Icon is a general-purpose programming language descended from SNOBOL4 and designed for the processing of strings and lists. It's an interesting language, if you are familiar with SNOBOL4, think of the pattern matching facility extended to the whole language. If you are a Prolog programmer, think of the Prolog evaluation mechanism (success or failure with backtracking) with general assignment instead of resolution. In either case, you also have to add that Icon expressions return values while SNOBOL4 patterns and Prolog clauses do not. If you don't follow the above, how about this: Icon is a language where all expressions produce zero or more values. There aren't any statements like in C or Pascal, only expressions. There _is_ a while- expression, an if-expression, etc. When any expression fails to produce a result, it attempts to _resume_ a preceding expression for another value. For example find(s1,s2) produces the first position in the string s2 that matches the string s1. But since expressions can produce 0 or more results, if s2 does not occure in s1, the expression fails. _And_, if s1 occurs more than once in s2, a seperate result is produced for each position. This obviously will not make much sense without a lot more explanation and examples. I recommend the book Ralph E. Griswold, Madge T. Griswold. _The Icon Programming Language_. Prentice Hall, 1983. Icon is implemented for a large number of systems including IBM 370, MSDOS, BSD Unix, VMS and about 20 more. For information on how to get an Icon interpreter (public domain, free except for distribution costs, written in C) contact icon-project@arizona.edu or ihnp4!arizona!icon-project or Icon Project Department of Computer Science Gould-Simpson Science Building The University of Arizona Tucson, AZ 85721 David Gudeman Department of Computer Science gudeman@arizona.edu Gould-Simpson Science Building ihnp4!arizona!gudeman The University of Arizona 602-621-2858 Tucson, AZ 85721
gudeman@arizona.edu (David Gudeman) (04/08/87)
I got a little carried away on my list of Icon distributions, and have since been corrected. Here's the _real_ list of distributions. You can consider it reliable since it's from Ralph Griswold, the inventor and distributor of Icon. UNIX most all computers and flavors VMS VAX MS-DOS all computers Macintosh Atari