FOR TRANSIT (also incorrectly FORTRANSIT) is a subset of the FORTRAN

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for the

IBM 650 The IBM 650 Magnetic Drum Data-Processing Machine is an early digital computer produced by IBM in the mid-1950s. It was the first mass-produced computer in the world. Almost 2,000 systems were produced, the last in 1962, and it was the firs ...

Magnetic Drum Data-Processing Machine, developed by a group led by

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. FORTRAN, the first

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, was developed for the

IBM 704 The IBM 704 is the model name of a large digital computer, digital mainframe computer introduced by IBM in 1954. Designed by John Backus and Gene Amdahl, it was the first mass-produced computer with hardware for floating-point arithmetic. The I ...

in 1957, at the same time

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wanted to provide something similar for customers of the older, less powerful, but popular 650—eventually over 2000 650s were sold. FOR TRANSIT was

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with 704 FORTRAN with some restrictions. For example variable names could only be five characters rather than six, and arrays could have a maximum of two dimensions instead of three. FOR TRANSIT was a

multi-pass compiler A multi-pass compiler is a type of compiler that processes the source code or abstract syntax tree of a program several times. This is in contrast to a one-pass compiler, which traverses the program only once. Each pass takes the result of the prev ...

. The first pass translated the source to an intermediate language, IT (Internal Translator), written by

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and others at the

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in 1957. The second pass compiled the IT into SOAP assembler code, and finally the SOAP code was assembled into the

machine language In computer programming, machine code is computer code consisting of machine language instructions, which are used to control a computer's central processing unit (CPU). For conventional binary computers, machine code is the binaryOn nonb ...

object program. FOR TRANSIT was never ported beyond the 650, as newer machines had the resources to run a full FORTRAN compiler. The name ''FOR TRANSIT'' might have one or more of three meanings: * FORTRAN-S(oap)-IT, describing the translation process * FOR TRANSIT(ion), indicating that it was intended to ease upgrades to the 704 * FORTRAN's IT, in the sense of adding a FORTRAN front-end to the IT compiler

References

External links

* Fortran programming language family IBM software Computer-related introductions in 1957 IBM mainframe software {{prog-lang-stub