In computing TMG (TransMoGrifier) is a recursive descent

compiler-compiler In computer science, a compiler-compiler or compiler generator is a programming tool that creates a Parsing#Computer_languages, parser, interpreter (computer software), interpreter, or compiler from some form of formal description of a programm ...

developed by Robert M. McClure and presented in 1965. TMG ran on systems including

OS/360 OS/360, officially known as IBM System/360 Operating System, is a discontinued batch processing operating system developed by IBM for their then-new System/360 mainframe computer, announced in 1964; it was influenced by the earlier IBSYS/IBJOB a ...

and early

Unix Unix (, ; trademarked as UNIX) is a family of multitasking, multi-user computer operating systems that derive from the original AT&T Unix, whose development started in 1969 at the Bell Labs research center by Ken Thompson, Dennis Ritchie, a ...

. It was used to build EPL, an early version of

PL/I PL/I (Programming Language One, pronounced and sometimes written PL/1) is a procedural, imperative computer programming language initially developed by IBM. It is designed for scientific, engineering, business and system programming. It has b ...

Douglas McIlroy Malcolm Douglas McIlroy (born 1932) is an American mathematician, engineer, and programmer. As of 2019 he is an Adjunct Professor of Computer Science at Dartmouth College. McIlroy is best known for having originally proposed Unix pipelines and de ...

ported TMG to an early version of Unix. According to

Ken Thompson Kenneth Lane Thompson (born February 4, 1943) is an American pioneer of computer science. Thompson worked at Bell Labs for most of his career where he designed and implemented the original Unix operating system. He also invented the B (programmi ...

, McIlroy wrote TMG in TMG on a piece of paper and "decided to give his piece of paper his piece of paper," hand-compiling

assembly language In computing, assembly language (alternatively assembler language or symbolic machine code), often referred to simply as assembly and commonly abbreviated as ASM or asm, is any low-level programming language with a very strong correspondence bet ...

that he entered and assembled on Thompson's

system running on

PDP-7 The PDP-7 is an 18-bit computing, 18-bit minicomputer produced by Digital Equipment Corporation as part of the Programmed Data Processor, PDP series. Introduced in 1964, shipped since 1965, it was the first to use their Flip-Chip module, Flip- ...

. Thompson used TMG in 1970 as a tool to offer Fortran, but due to memory limitations of PDP-7 ended up creating the B programming language which was much influenced by

BCPL BCPL ("Basic Combined Programming Language") is a procedural, imperative, and structured programming language. Originally intended for writing compilers for other languages, BCPL is no longer in common use. However, its influence is still f ...

. The recursive descent algorithm of TMG was studied formally by Alexander Birman and

Jeffrey Ullman Jeffrey David Ullman (born November 22, 1942) is an American computer scientist and the Stanford W. Ascherman Professor of Engineering, Emeritus, at Stanford University. His textbooks on compilers (various editions are popularly known as the dr ...

. The formal description of the algorithms was named ''TMG recognition scheme'' (or simply ''TS'').

References

External links

* * Compiling tools Parser generators Low-level programming languages {{Prog-lang-stub

See also

References

External links