Macros for machine-independent software

Macros are commonly acclimated to map a abbreviate cord (macro invocation) to a best arrangement of instructions. Another, beneath common, use of macros is to do the reverse: to map a arrangement of instructions to a macro string. This was the access taken by the STAGE2 Mobile Programming System, which acclimated a abecedarian macro compiler (called SIMCMP) to map the specific apprenticeship set of a accustomed computer to analogue machine-independent macros. Applications (notably compilers) accounting in these machine-independent macros can again be run after change on any computer able with the abecedarian macro compiler. The aboriginal appliance run in such a ambience is a added adult and able macro compiler, accounting in the machine-independent macro language. This macro compiler is activated to itself, in a bootstrap fashion, to aftermath a aggregate and abundant added able adaptation of itself. The advantage of this access is that circuitous applications can be ported from one computer to a actual altered computer with actual little accomplishment (for anniversary ambition apparatus architecture, aloof the autograph of the abecedarian macro compiler).1011 The appearance of avant-garde programming languages, conspicuously C, for which compilers are accessible on around all computers, has rendered such an access superfluous. This was, however, one of the aboriginal instances (if not the first) of compiler bootstrapping.