REXX: REstructured eXtended eXecutor

REXX, short for REstructured eXtended eXecutor, is a high-level scripting and macro programming language designed for ease of use, text processing, and automation on IBM mainframes, PC platforms, and various operating systems. It is widely used for scripting administrative tasks, automating repetitive operations, and building system utilities. Developers can download REXX interpreters and environments such as Regina REXX, IBM’s Object REXX, and Open Object REXX for Windows, Linux, and z/OS systems.

REXX exists to provide a simple, readable, and consistent language for text manipulation and system automation. Its design philosophy emphasizes minimal syntax, readability, and ease of learning while remaining powerful for complex operations. By unifying string handling, control structures, and function definitions in a straightforward syntax, REXX solves the problem of maintaining cumbersome scripts and macros across different environments.

REXX: Variables and Basic Syntax

REXX supports dynamically typed variables and straightforward assignment for quick script development.

employeeName = 'Alice'
salary = 75000

say 'Employee:' employeeName 'Salary:' salary

Variables are declared by simple assignment, and say outputs text and values. This simplicity parallels scripting approaches in Python and Perl.

REXX: Procedures and Subroutines

REXX allows modularization through procedures and subroutines to encapsulate reusable logic.

parseName: procedure
  parse arg name
  say 'Parsed name:' name
return

call parseName 'Alice'

Procedures improve readability and modularity. They are analogous to functions in Python or Ruby, allowing code reuse and clearer structure.

REXX: Conditional Logic

REXX supports conditional branching using if-then-else statements for decision-making.

if salary > 70000 then
    category = 'High'
else
    category = 'Moderate'

say 'Salary Category:' category

Conditional logic allows categorization and program flow control. This is similar to control structures in Python or Ruby.

REXX: Loops and Iteration

REXX provides looping constructs for iterating over data sequences.

do i = 1 to 3
    say 'Iteration:' i
end

Loops using do enable repetitive tasks, much like Python for loops or Ruby each iterators, offering concise iteration over sequences.

REXX: String and Data Manipulation

REXX excels at text processing, providing built-in functions for substring extraction, parsing, and pattern matching.

fullName = 'Alice Smith'
firstName = substr(fullName, 1, 5)
say 'First Name:' firstName

Functions like substr and parsing operations allow powerful text handling, comparable to string manipulation in Python and Perl.

Overall, REXX provides a simple, readable, and versatile scripting environment. When used alongside Python, Perl, and Ruby, it enables developers and system administrators to automate tasks, process text, and implement system utilities efficiently. Its combination of clear syntax, procedural abstraction, looping constructs, and string manipulation ensures REXX remains a reliable language for cross-platform scripting and automation.

Procedure

Variable

Function