COWSEL
Encyclopedia
COWSEL is a programming language
designed between 1964 and 1966 by Robin Popplestone
. It was based on a RPN
form of Lisp
combined with some ideas from CPL
.
COWSEL was initially implemented on a Ferranti Pegasus computer at the University of Leeds
and on a Stantec Zebra at the Bradford Institute of Technology; later, Rod Burstall
implemented it on an Elliot 4120 at the University of Edinburgh
.
COWSEL was renamed POP-1 during the summer of 1966 and development continued under that name from then on.
lambda x y
comment Is x a member of list y;
define y atom then *0 end
y hd x equal then *1 end
y tl -> y repeat up
Note that keywords were also underlined in the original printouts. Popplestone used a Flexowriter with underscoring for syntax highlighting
.
Programming language
A programming language is an artificial language designed to communicate instructions to a machine, particularly a computer. Programming languages can be used to create programs that control the behavior of a machine and/or to express algorithms precisely....
designed between 1964 and 1966 by Robin Popplestone
Robin Popplestone
Robin John Popplestone was a pioneer in the fields of machine intelligence and robotics. He developed the POP programming languages....
. It was based on a RPN
Reverse Polish notation
Reverse Polish notation is a mathematical notation wherein every operator follows all of its operands, in contrast to Polish notation, which puts the operator in the prefix position. It is also known as Postfix notation and is parenthesis-free as long as operator arities are fixed...
form of Lisp
Lisp programming language
Lisp is a family of computer programming languages with a long history and a distinctive, fully parenthesized syntax. Originally specified in 1958, Lisp is the second-oldest high-level programming language in widespread use today; only Fortran is older...
combined with some ideas from CPL
Combined Programming Language
CPL was a multi-paradigm programming language, that was developed in the early 1960s.- Design :...
.
COWSEL was initially implemented on a Ferranti Pegasus computer at the University of Leeds
University of Leeds
The University of Leeds is a British Redbrick university located in the city of Leeds, West Yorkshire, England...
and on a Stantec Zebra at the Bradford Institute of Technology; later, Rod Burstall
Rod Burstall
Rodney Martineau Burstall is one of four founders of the Edinburgh Laboratory for Foundations of Computer Science.He was an early and influential proponent of functional programming, pattern matching, and list comprehension, and is known for his work with Robin Popplestone on POP, an innovative...
implemented it on an Elliot 4120 at the University of Edinburgh
University of Edinburgh
The University of Edinburgh, founded in 1583, is a public research university located in Edinburgh, the capital of Scotland, and a UNESCO World Heritage Site. The university is deeply embedded in the fabric of the city, with many of the buildings in the historic Old Town belonging to the university...
.
COWSEL was renamed POP-1 during the summer of 1966 and development continued under that name from then on.
Example code
function memberlambda x y
comment Is x a member of list y;
define y atom then *0 end
y hd x equal then *1 end
y tl -> y repeat up
Note that keywords were also underlined in the original printouts. Popplestone used a Flexowriter with underscoring for syntax highlighting
Syntax highlighting
Syntax highlighting is a feature of some text editors that display text—especially source code—in different colors and fonts according to the category of terms. This feature eases writing in a structured language such as a programming language or a markup language as both structures and...
.
See also
- POP-2POP-2POP-2, often referred to as POP2 was a programming language developed around 1970 from the earlier language POP-1 by Robin Popplestone and Rod Burstall at the University of Edinburgh. It drew roots from many sources: the languages LISP and ALGOL 60, and theoretical ideas from Landin...
programming language - POP-11POP-11POP-11 is a reflective, incrementally compiled programming language with many of the features of an interpreted language. It is the core language of the Poplog programming environment developed originally by the University of Sussex, and recently in the at the...
programming language - PoplogPoplogPoplog is a powerful multi-language, multiparadigm, reflective, incrementally compiled software development environment, originally created in the UK for teaching and research in Artificial Intelligence at the University of Sussex.-History:...
programming environment