After completing this course the student should be able to:
 

	Code basic REXX execs
	Use variables expressions and operators
	Include conditional and looping instructions
	Utilize the stack
	Pass information to and from an exec
	Perform comparison formatting and string manipulating functions
	Use compound variables
	Employ various ways of parsing
	Debug execs using TRACE

Introducing REXX
Introduces you to the REXX programming language and its features.
 

	REXX execs Features and components of REXX.  Recognizing a REXX exec.  Basic syntax rules.
	Variables Expressions and Operators Assigning names and values to variables.  Using REXX to perform arithmetic calculations.  Precedence of arithmetic operators used in REXX.
	More Operators Using the comparative logical and concatenation operators.

Basic REXX Instructions
Presents basic REXX instructions.  Explains how to store data on the stack.
 

	Writing to the Terminal Writing to the terminal with a SAY instruction.
	Reading from the Terminal Reading from the terminal with the PULL instruction.  Retrieving data from the command line using the ARG instruction.
	Selection Techniques Controlling the logic flow within REXX by using IF/THEN/ELSE instructions.  Using the NOP instruction.  How to unconditionally leave a REXX exec with the EXIT instruction.
	Simple DO Loops Using simple DO loops.  Adding the LEAVE instruction to terminate a DO FOREVER group.
	Stack Definition of a stack.  Manipulation of the stack using PULL PUSH and QUEUE.

Program Control
Explores more complex selection techniques and DO structures.  Discusses subroutines and the interrupt instruction SIGNAL.
 

	Advanced Selection Techniques Using SELECT/WHEN/OTHERWISE in a REXX exec.
	Complex DO Structures How to manage controlled repetitive loops.  How to nest loops.  Use of the ITERATE instruction.
	Subroutines Coding simple subroutines in a REXX exec.  Passing data between a calling exec and subroutine.  Using the PROCEDURE instruction with or without the EXPOSE option.
	Control Jumps Using the SIGNAL instruction to alter the flow of program control.

REXX Functions
Covers the three categories of REXX functions.
 

	Comparison/Formatting Calling a function in a REXX exec.  Employing comparison functions: COMPARE and DATATYPE.  Using formatting functions: CENTER LEFT RIGHT COPIES and SPACE.
	String Manipulating Using string manipulating functions: STRIP SUBSTR SUBWORD OVERLAY LENGTH WORDS WORDLENGTH WORD WORDINDEX WORDPOS and POS. Advanced Program Features Describes advanced features in REXX programming.
	Compound Variables and Arrays Using compound variables to set up arrays and lists of variables.  Using the stem to change a collection of variables.
	The PARSE Instruction Using PARSE PULL PARSE VAR and PARSE VALUE in a REXX exec.
	Using the Stack Adding and dropping buffers from the stack.  How PUSH PULL and QUEUE act on the buffers.  Using QUEUE() to return the number of entries in the stack.
	Debugging Using the TRACE instruction to debug a REXX exec.  Names of TRACE options.