Macros and Edit Macros

ISPF edit macros are scripts that automate editing tasks in the ISPF editor. They can be written in REXX (Restructured Extended Executor) or CLIST (Command List) languages and allow you to perform complex operations, apply consistent formatting, and automate repetitive tasks. This tutorial covers the basics of ISPF edit macros, including REXX and CLIST macros, how to create and use them, and common use cases.

Understanding edit macros is valuable for automating repetitive editing tasks, standardizing code formatting, and performing complex operations that would be time-consuming to do manually. Macros extend the capabilities of the ISPF editor and can significantly improve productivity.

Understanding Edit Macros

Edit macros are scripts that run within the ISPF editor environment.

What are Edit Macros?

Edit macros are:

• Scripts written in REXX or CLIST
• Stored in partitioned data set libraries
• Invoked from the editor command line
• Capable of reading and modifying the file being edited
• Tools for automating editing tasks

Benefits of Edit Macros

Edit macros provide:

• Automation: Automate repetitive editing tasks
• Consistency: Apply consistent formatting and standards
• Efficiency: Perform complex operations quickly
• Customization: Create custom editing tools for your needs
• Productivity: Save time on routine editing tasks

When to Use Edit Macros

Use edit macros when:

• You have repetitive editing tasks
• You need consistent formatting
• You want to automate complex operations
• You need to apply standards across multiple files
• You want to extend editor capabilities

REXX Edit Macros

REXX (Restructured Extended Executor) is a powerful scripting language for writing edit macros.

REXX Overview

REXX provides:

• Strong string handling capabilities
• Structured programming features
• Easy-to-learn syntax
• Broad capabilities for complex operations
• Good integration with ISPF

REXX Macro Structure

A basic REXX edit macro structure:

1
2
3
4
5
6
/* REXX Edit Macro */
Address ISREDIT
"MACRO"
"PROCESS RANGE ALL"
/* Macro logic here */
Exit

REXX Macro Example

A simple REXX macro to add line numbers:

1
2
3
4
5
6
7
8
/* REXX Macro: Add line numbers */
Address ISREDIT
"MACRO"
"PROCESS RANGE ALL"
Do i = 1 to 100
  "LINE_AFTER" i "SET" i
End
Exit

REXX ISPF Interface

REXX macros interact with ISPF through:

• Address ISREDIT: Sets the environment to ISPF editor
• ISREDIT commands: Commands to interact with the editor
• Variable access: Access to editor variables and file content
• Line operations: Commands to read, modify, insert, and delete lines

Common REXX ISREDIT Commands

Common commands include:

• LINE_AFTER n: Insert line after line n
• LINE_BEFORE n: Insert line before line n
• LINE_DELETE n: Delete line n
• LINE_GET n: Get line n into a variable
• LINE_PUT n: Replace line n with variable content
• FIND: Find text in the file
• CHANGE: Change text in the file

CLIST Edit Macros

CLIST (Command List) is an older TSO command language for writing edit macros.

CLIST Overview

CLIST provides:

• Simpler syntax than REXX
• Basic programming capabilities
• Integration with TSO commands
• Suitable for simpler tasks
• Widely available on mainframe systems

CLIST Macro Structure

A basic CLIST edit macro structure:

1
2
3
4
5
6
PROC 0
CONTROL MAIN NOMSG
ISREDIT MACRO
ISREDIT PROCESS RANGE ALL
/* Macro logic here */
END

CLIST Macro Example

A simple CLIST macro example:

1
2
3
4
5
6
7
PROC 0
CONTROL MAIN NOMSG
ISREDIT MACRO
ISREDIT PROCESS RANGE ALL
ISREDIT FIND 'OLD' FIRST
ISREDIT CHANGE 'OLD' 'NEW' ALL
END

CLIST ISPF Interface

CLIST macros interact with ISPF through:

• ISREDIT commands: Commands prefixed with ISREDIT
• Variable handling: CLIST variable syntax
• Control flow: CLIST control structures
• TSO integration: Ability to call TSO commands

REXX vs CLIST

Understanding the differences helps you choose the right language.

REXX Advantages

REXX is better for:

• Complex string manipulation
• Structured programming
• Modern programming practices
• Complex logic and algorithms
• Better error handling

CLIST Advantages

CLIST is better for:

• Simple tasks
• Quick scripts
• Basic operations
• When REXX is not available
• Legacy system compatibility

Choosing Between REXX and CLIST

Choose based on:

• Complexity of the task
• Available languages on your system
• Your familiarity with each language
• Requirements of the macro
• Maintenance and support considerations

Creating Edit Macros

Creating edit macros involves writing the script and storing it in a macro library.

Macro Library Setup

To create macros:

• Allocate a partitioned data set (PDS) or PDSE for macros
• Ensure the library is in your SYSPROC or SYSEXEC allocation
• Create members in the library for each macro
• Store REXX macros with appropriate attributes

Writing a REXX Macro

Steps to write a REXX macro:

• Open the macro library in the ISPF editor
• Create a new member with the macro name
• Write the REXX code with Address ISREDIT
• Use ISREDIT commands to interact with the editor
• Save the member

Writing a CLIST Macro

Steps to write a CLIST macro:

• Open the macro library in the ISPF editor
• Create a new member with the macro name
• Write the CLIST code with ISREDIT commands
• Use CLIST syntax for control flow
• Save the member

Invoking Edit Macros

Edit macros are invoked from the ISPF editor command line.

Basic Invocation

To invoke a macro:

• Type the macro name on the command line
• Add any parameters if the macro accepts them
• Press Enter to execute
• The macro runs and performs its operations

Invocation Example

Invoking a macro named "FORMAT":

1
Command ===> FORMAT

Invoking a macro with parameters:

1
Command ===> FORMAT 10 20

Macro Parameters

Macros can accept parameters:

• Parameters are passed as arguments
• REXX accesses them via ARG or PARSE ARG
• CLIST accesses them via &1, &2, etc.
• Parameters are separated by spaces

Common Use Cases

Here are common use cases for edit macros.

Code Formatting

Macros can format code:

• Apply consistent indentation
• Standardize spacing
• Align columns
• Apply coding standards

Header/Footer Insertion

Macros can insert headers or footers:

• Add standard file headers
• Insert copyright notices
• Add modification history
• Insert standard footers

Bulk Find and Replace

Macros can perform bulk operations:

• Complex find and replace patterns
• Conditional replacements
• Multi-step transformations
• Pattern-based modifications

Code Generation

Macros can generate code:

• From templates
• Based on parameters
• Following patterns
• With standard structures

Best Practices

Following best practices helps you create effective edit macros:

• Test Thoroughly: Test macros on sample files before using on important files
• Handle Errors: Include error handling in your macros
• Document Macros: Document what macros do and how to use them
• Use Meaningful Names: Choose clear, descriptive macro names
• Validate Input: Validate parameters and file content
• Make Macros Reusable: Design macros to work with different files
• Keep Macros Simple: Avoid overly complex macros when possible
• Version Control: Maintain versions of macros for tracking changes

Macro Library Management

Managing your macro library effectively.

Library Organization

Organize your macro library:

• Group related macros together
• Use consistent naming conventions
• Document macro purposes
• Maintain a macro index or catalog

Macro Maintenance

Maintain your macros:

• Update macros as needs change
• Fix bugs and improve functionality
• Remove obsolete macros
• Keep documentation current

Explain Like I'm 5: Edit Macros

Think of edit macros like special helpers that do editing tasks for you:

• Edit Macros are like having a robot helper. You tell the robot "format my code!" or "add headers to my file!" and the robot does it automatically. It's like having a helper that knows how to do special editing tasks!
• REXX and CLIST are like different languages you can use to talk to the robot. REXX is like a more advanced language that can do complex things, while CLIST is like a simpler language for basic tasks. Both can tell the robot what to do!
• Macro Library is like a toolbox where you keep all your robot helpers. Each helper (macro) is stored in the toolbox, and when you need one, you call its name and it comes to help!
• Invoking a Macro is like calling your helper. You type the helper's name on the command line, and the helper comes and does the work for you, like calling a friend to help with a task!

So edit macros are like special robot helpers that you can create and call to do editing tasks automatically, making your work faster and easier!

Practice Exercises

Complete these exercises to reinforce your understanding of edit macros:

Exercise 1: Understanding Macros

Research available edit macros: explore your system's macro libraries, identify existing macros, understand what they do, and learn how to invoke them. Build familiarity with macro concepts.

Exercise 2: Simple REXX Macro

Create a simple REXX macro: write a basic REXX macro that performs a simple operation (like adding a comment line), test it on a sample file, and verify it works correctly. Learn basic REXX macro structure.

Exercise 3: Simple CLIST Macro

Create a simple CLIST macro: write a basic CLIST macro that performs a simple operation, test it on a sample file, and verify it works correctly. Learn basic CLIST macro structure.

Exercise 4: Macro Invocation

Practice invoking macros: invoke existing macros from the command line, try macros with parameters, observe macro behavior, and understand how macros interact with the editor.

Exercise 5: Macro Library Exploration

Explore macro libraries: browse macro libraries on your system, identify useful macros, read macro documentation if available, and understand how macros are organized and stored.

Related Concepts