- MACRO PROGRAMMING LANGUAGE LIST SOFTWARE
- MACRO PROGRAMMING LANGUAGE LIST SERIES
If the macro definition contained both &ID and &ID1 as parameters, the situation would be ambiguous. The body of the macro definition might contain a statement like “LDA X&ID1” in which the parameter &ID is concatenated after the character string X and before the character string 1. MACRO PROGRAMMING LANGUAGE LIST SERIES
If similar processing is to be performed on each series of variables, the programmer might want to incorporate this processing in to a macro instruction. Most macro processors allow parameters to concatenated with other character strings. Machine-Independent Macro Processor Features When a macro invocation statement is recognized, the arguments are stored in ARGTAB according to their position in the argument listĪlgorithm for a One-pass Macro Processor(3/1)Īlgorithm for a One-pass Macro Processor(3/2)Īlgorithm for a One-pass Macro Processor(3/3). The third data structure is an argument table (ARGTAB), which is used during the expansion of macro invocations. For each macro instruction defined NAMTAB contains pointers to the beginning and end of the definition in DEFTAB. The macro names are entered into NAMTAB, which serves as an index to DEFTAB. The macro definitions themselves are stored in definition table (DEFTAB), which contains the macro prototype and the statements that make up the macro body. 
A macro invocation statement gives the name of the macro instruction being invoked and the arguments to be used in expanding the macro.The MEND assembler directive marks the end of the macro definition.Each parameter begins with the character &.
The entries in the operand field identify the parameter of the macro instruction. The symbol in the label field is the name of the instruction. The MACRO statement identifies the beginning of a macro definition. The functions of a macro processor essentially involve the substitution of one group of characters or lines for another. The macro processor replaces each macro instruction with the corresponding group of source language statement, this is called expanding macros. A macro represents a commonly used group of statements in the source programming language In the Customize the Ribbon category, in the Main Tabs list, select the Developer check box, and then click Save. MACRO PROGRAMMING LANGUAGE LIST SOFTWARE
Chapter 4 Macro Processors System Software Chih-Shun Hsu
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