Hairy Control Structure
According to Hewitt, Peter Landin had introduced an even more powerful control structure using his "J" (for Jump) operator that could perform a non-local goto into the middle of a procedure invocation. In fact the "J" operator could jump back into the middle of a procedure invocation even after it had already returned. Drew McDermott and Gerald Sussman called Landin's concept the "Hairy Control Structure" and used it in the form of a nonlocal goto for the Conniver programming language. Scott Fahlman used Conniver in his planning system for robot construction tasks. This is related to what are now called re-invocable continuations.
Difficulties in communication were a root cause of the control structure difficulties.
Read more about this topic: Planner (programming Language)
Famous quotes containing the words hairy, control and/or structure:
“Civilization must be destroyed. The hairy saints
Of the North have earned this crumb by their complaints.”
—Wallace Stevens (1879–1955)
“To try to control a nine-month-old’s clinginess by forcing him away is a mistake, because it counteracts a normal part of the child’s development. To think that the child is clinging to you because he is spoiled is nonsense. Clinginess is not a discipline issue, at least not in the sense of correcting a wrongdoing.”
—Lawrence Balter (20th century)
“Slumism is the pent-up anger of people living on the outside of affluence. Slumism is decay of structure and deterioration of the human spirit. Slumism is a virus which spreads through the body politic. As other “isms,” it breeds disorder and demagoguery and hate.”
—Hubert H. Humphrey (1911–1978)