- Author
- Not stated (Wikipedia, many editors)
- Published
- Last edited 1 November 2026
- Kind
- Encyclopedia article
- Original
- en.wikipedia.org/wiki/COMEFROM
- Subject
- Programming languages and types
What it is
Wikipedia editors describe a statement that makes control jump away from a named point. The article covers history, semantics and four examples.
What it says
- COMEFROM sends control to the statement after it when a named point is reached.
- Goto depends on local code structure, while COMEFROM depends on global structure.
- The interpreter must scan for COMEFROM statements. Nothing near a jump point shows a jump.
- Semantics vary by language, including whether the jump happens before or after the target statement.
- A 1973 Datamation article by R. Lawrence Clark answered Dijkstra's goto letter, and C-INTERCAL later implemented COMEFROM.
- Richie Hindle published a working Python COMEFROM on 1 April 2004 using debugger hooks.
- In OS/360 Fortran G, the debug AT statement acts like COMEFROM.
What evidence it gives
It cites a Datamation article, a SIGPLAN Notices paper, an IBM manual and a newsletter. It gives code in a hypothetical BASIC, Python, Ruby and OS/360 Fortran G.
Interests and limits
Wikipedia is edited by volunteers and one claim is marked citation needed. The examples were not run. The article treats COMEFROM mainly as humor.