![]() They belong to entirely different families, but we use them as if they are complementary siblings. For example, macro function %upcase() is pre-built, while macro function %lowcase() is auto-call macro function. Here is a selected list of auto-call macros provided with SAS software.įrom the usage standpoint, you will not notice any difference between the pre-built and the auto-call macro functions. For example, for my SAS BASE installation the auto-call macro library is in the following folder:Ĭ:\Program Files\SASHome\SASFoundation\9.4\core\sasmacro They may include several macro libraries depending on the SAS products licensed at your site. ![]() The auto-call macro functions come with your SAS software installation and usually pre-configured for you by setting MAUTOSOURCE and SASAUTOS= macro system options. The main difference from the pre-built macro functions is that the auto-call macro functions are program samples of the user-defined macro functions that are written in SAS macro language and made available to you without having to define or include them in your programs. These macro functions supplement the pre-built macro functions. Auto-call macro functionsĪuto-call macros, some of them are type 1 (macros), and some – type 2 (macro functions) such as %cmpres, %left, %lowcase, %trim, %verify, etc. Here is a complete list of the pre-built SAS macro functions. These are such macro functions as %eval, %length, %quote, %scan, %str, %sysfunc, %upcase, etc. Pre-built macro functions that are part of the macro processor. SAS macro functions may come from the following three sources. Among others, one of the most powerful is %SYSFUNC macro function which brings a wealth of SAS language functions into SAS macro language. You can use existing macro functions in your own macro function definition. SAS users may define their own macro functions, but in doing so you may not utilize any SAS language syntax only SAS macro language syntax is allowed. As any SAS macros, SAS macro functions can have any number (zero or more) of positional or/and named parameters (arguments). In other words, it is the type 2 macro described above. ![]() SAS macro function is a SAS macro that generates a value. This type does not generate any SAS executable code, just a value. Macros that generate some string values which can be used as part of SAS programming language code or data values, but they are not complete SAS statements or steps.Macros that generate some SAS programming language code which can span across SAS statements or steps.There are two distinct types of SAS macros: Clear understanding of this difference is the key to becoming a successful SAS programmer. In this analogy meal=code, cooking=SAS macro language, eating=SAS programming language. ![]() The difference between them is like a difference between cooking a meal and eating the meal. SAS macro language (comprised of %LET, %IF, %DO, macro functions etc.) which is processed separately from and before SAS compiler executes SAS programming language code.SAS programming language (comprised of DATA steps, PROC steps and global statements such as LIBNAME, OPTIONS, TITLE etc.).In other words, SAS code is a combination of two distinct languages: SAS programming languageĪ SAS program usually consists of two, often interwoven layers – macro layer and non-macro layer, each with its own syntax and its own timing of compilation and execution. If found, SAS software activates macro processor which resolves and substitutes those macro references according to the macro language syntax before SAS compiles and executes your programming steps. Generally, SAS software processes your SAS program step by step, first scanning it for macro language objects - macro variables referenced as &somename, and macros referenced as %somename. Related blog post: Multi-purpose macro function for getting information about data sets Macro language and macro processor It allows SAS users to modularize programming code with “once written – many times used” components, and in many cases automatically generate data-driven SAS code. SAS® Macro Language immensely empowers SAS programmers with versatility and efficiency of their code development. ![]()
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