File X.html    Author McKeeman    Copyright © 2007    index

... the art of language design becomes
the art of designing a powerful and systematic language
primarily from those elements which can be processed elegantly by a translator...
-- Edsger Dijkstra, foreword to Algol 60 Implementation

X is a complete programming language based on Edsger Dijkstra's book A Discipline of Programming. X is implemented by the xcom compiler.

• MATLAB Command Line
• Typeset Examples of X
• Bigger Example of X
• X Reference Manual
• Programming Exercises
• X Debugging
• X and xcom Performance

The use of grammars to describe programming languages is ubiquitous. Assuming you already intuitively understand grammatical notation, here is a complete Cfg for X. The X Cfg is an essential part of the xcom compiler. You will be expected to modify the X Cfg as a first step in modifying xcom. Later, grammars will be studied for themselves in detail. Developing some skill in language design is also recommended.