Index

This is an introductory tutorial to the Rexx programming language.

Alphabetic instruction index Alphabetic built-in function index Syntax summary -- quick reference

The following links are organized to introduce concepts for new Rexx programmers. Proceed down the columns and then to the right. Advanced programmers can reference a specific link, as necessary.

Hint: you can use the Tab key to sequence through the links.

Program structure Instruction elements and tokens Instruction terminators Comments Line continuation Symbolic variables Expressions Expression operators Operator precedence Say instruction String concatenation Assignment instruction Instruction classification Introductory examples Labels Boolean expressions If instruction Do nothing instruction -- Nop

Do instruction -- simple group Iterative do instructions Conditional loops Iterate, advanced iteration instruction Leave, advanced iteration instruction Select instruction End instruction Procedure instruction Call instruction Function calls Built-in functions Interpret instruction Signal instruction Condition handling Symbol removal instruction -- Drop Procedure completion instructions -- Exit / Return Parse instructions -- Arg / Parse / Pull Parse templates Introductory tutorial to parsing

System command instruction Changing command environment -- Address instruction Changing numeric computation options -- Numeric instruction Changing interpretation options -- Options instruction Adding lines to the data queue -- Push / Queue instructions Trace instruction External data queue Special variables -- RC, RESULT, and SIGL Error codes Performance hints Advanced examples A hand of cards example Rexx control flow synopsis program

2 Introduction:

The Rexx language was the first scripting language. Many consider it one of the best.

Inventor Michael Cowlishaw documented the language in his book The Rexx Language : A Practical Approach to Programming, 2nd Edition. The book was published in 1990 by Prentice-Hall.

You can download a free copy of the book by clicking here.

The Rexx Programmer's Reference is a very complete 750 page book covering all aspects of Rexx. A newly revised and updated 2nd edition was published in 2025. You can download a free copy by clicking here.

You may purchase a print copy by clicking here.

For more information on Rexx, visit the website RexxInfo.org. It offers articles, reference, tools, downloads, and more, all of it free and open source.

Kilowatt Software now offers roo!(TM) --an object-oriented Rexx interpreter.