In computer programming, COMEFROM is a control flow structure used in some programming languages. Its purpose is roughly the opposite of GOTO, in that it takes the execution state from any arbitrary point in code to a COMEFROM statement. Depending on the language used, multiple COMEFROMs referencing the same departure point may be invalid, be non-deterministic, or induce parallel execution. It was initially seen in lists of joke assembly language instructions (as 'CMFRM') and was elaborated upon in a Datamation article by R. Lawrence Clark in 1973. COMEFROM was eventually implemented in the esoteric programming language INTERCAL. One implementation of FORTRAN also included it, under the name "AT", as a debugging aid, with dire warnings against using it in production code. A computer program (often simply called a program) is an example of computer software that prescribes the actions (computations) that are to be carried out by a computer. ... In computer science and in computer programming, statements in pseudocode or in a program are normally obeyed one after the other in the order in which they are written (sequential flow of control). ... A programming language or computer language is a standardized communication technique for expressing instructions to a computer. ... This page is about the programming command. ... Assembly language or simply assembly is a human-readable notation for the machine language that a specific computer architecture uses. ... Datamation was a computer magazine published in the United States between 1957 and 1997. ... Among some hackers and hobbyists, an esoteric programming language is a programming language designed as a test of the boundaries of computer programming language design, as a proof of concept, or as joke, and not with the intention of being adopted for real-world programming. ... INTERCAL is a programming language parody, the canonical esoteric programming language. ... Fortran (also FORTRAN) is a statically typed, compiled programming language originally developed in the 1950s and still heavily used for scientific computing and numerical computation half a century later. ... Debugging is a methodical process of finding and reducing the number of bugs, or defects, in a computer program or a piece of electronic hardware thus making it behave as expected. ...

External References

• COMEFROM Information Page (http://c2.com/cgi/wiki?ComeFrom)
• Datamation Article (http://www.fortran.com/fortran/come_from.html)
• Joke Assembler Instruction List Including CMFRM (http://home.online.no/~heberglu/funtext/89.htm)