Macros

Macro language" redirects here. For human macrolanguages, see ISO 639 macrolanguage.


jEdit's macro editor
A macro (short for "macroinstruction", from Greek μακρο- 'large') incomputer science is a rule or pattern that specifies how a certain input sequence (often a sequence of characters) should be mapped to a replacement input sequence (also often a sequence ofcharacters) according to a defined procedure. The mapping process that instantiates (transforms) a macro use into a specific sequence is known as macro expansion. A facility for writing macrosmay be provided as part of a software application or as a part of a programming language. In the former case, macros are used to make tasks using the application less repetitive. In thelatter case, they are a tool that allows a programmer to enable code reuse or even to design domain-specific languages.
Macros are used to make a sequence of computing instructionsavailable to the programmer as a single program statement, making the programming task less tedious and less error-prone.[1][2] (Thus, they are called "macros" because a big block of code can beexpanded from a small sequence of characters). Macros often allow positional or keyword parameters that dictate what the conditional assembler program generates and have been used tocreate entire programs or program suites according to such variables as operating system, platform or other factors. The term derives from "macro instruction", and such expansions wereoriginally used in generating assembly language code.
Contents [hide]
1 Keyboard and mouse macros
1.1 Application macros and scripting
1.1.1 Macro virus
2 Text substitution macros
2.1Embeddable languages
3 Procedural macros
4 Syntactic macros
4.1 Early Lisp macros
4.2 Hygienic macros
4.3 Applications
5 Macros for machine-independent software
6 See also
7 References