HLASM: V1R6 Language Ref

Source and library macro definitionsThe DOS/VSE assembler requires library macro definitions to be placed in themacro library in a special edited format. High Level Assembler does not requirethis. Library macro definitions must be placed in the macro library in sourcestatement format. If you wish to use edited macros in z/VSE you can provide aLIBRARY exit to read the edited macros and convert them into source statementformat. A library exit is supplied with z/VSE and is described in VSE/ESA Guide toSystem Functions.System macro instructionsThe macro instructions that correspond to macro definitions prepared by IBM arecalled system macro instructions. System macro instructions are described in theapplicable operating system manuals that describe macro instructions forsupervisor services and data management.Conditional assembly languageThe conditional assembly language is a programming language with most of thefeatures that characterize a programming language. For example, it provides:v Variablesv Data attributesv Expression computationv Assignment instructionsv Labels for branchingv Branching instructionsv Substring operators that select characters from a stringUse the conditional assembly language in a macro definition to receive input froma calling macro instruction. You can produce output from the conditional assemblylanguage by using the MNOTE instruction.Use the functions of the conditional assembly language to select statements forgeneration, to determine their order of generation, and to do computations thataffect the content of the generated statements.The conditional assembly language is described in Chapter 9, “How to writeconditional assembly instructions,” on page 315.Chapter 6. Introduction to macro language 239