Programming Guide - Actian

Chapter 17: Preprocessing Your 4GL CodeThis section contains the following topics:Preprocessor (see page 433)Error Processing (see page 439)This chapter describes the OpenROAD preprocessor and contains informationabout using include scripts and macro variables with the preprocessor.PreprocessorThe preprocessor provides the following extensions to 4GL that let you do thefollowing:• Include scripts of 4GL code anywhere in your frame script by using aninclude script that references the 4GL code• Use macro variables that you define or ones that are defined by thesystem• Specify conditional behavior for macro variables• Specify whether you want code to be included or excluded at compile timeThe preprocessor is invoked every time you compile a frame, procedure, oruser class. It processes OpenROAD preprocessor statements that you specifyin your scripts. These statements are:• #include• #define• #undef• #if – #endif• #ifdef – #endif• #ifndef – #endifThese statements and how to use them with include scripts and macrovariables are described in the following sections.Preprocessing Your 4GL Code 433