SAS 9.4 Macro Language, 5th Edition

Chapter 11

Writing Efficient and Portable

Macros

Writing Efficient and Portable Macros . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 143

Keeping Efficiency in Perspective . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 144

Writing Efficient Macros . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 144

Use Macros Wisely . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 144

Use Name Style Macros . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 145

Avoid Nested Macro Definitions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 145

Assign Function Results to Macro Variables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 146

Turn Off System Options When Appropriate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 147

Use the Stored Compiled Macro Facility . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 147

Centrally Store Autocall Macros . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 148

Other Useful Efficiency Tips . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 148

Storing Only One Copy of a Long Macro Variable Value . . . . . . . . . . . . . . . . . . . 149

Writing Portable Macros . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 150

Using Portable SAS Language Functions with %SYSFUNC . . . . . . . . . . . . . . . . 150

Example Using %SYSFUNC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 151

Using Automatic Variables with Host-Specific Values . . . . . . . . . . . . . . . . . . . . . 151

Example Using SYSPARM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 153

SYSPARM Details . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 154

SYSRC Details . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 154

Macro Language Elements with System Dependencies . . . . . . . . . . . . . . . . . . . . . 154

Host-Specific Macro Variables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 155

Naming Macros and External Files for Use with the Autocall Facility . . . . . . . . . 156

Writing Efficient and Portable Macros

The macro facility is a powerful tool for making your SAS code development more

efficient. But macros are only as efficient as you make them. There are several

techniques and considerations for writing efficient macros. You can extend the power of

the macro facility by creating macros that can be used on more than one host

environment. In order to do this, there are additional considerations for writing portable

macros.

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