Predicative programming
Encyclopedia
Predicative programming is a methodology for program specification
and refinement. The central idea of predicative programming is that each specification is a predicate (generally written as a boolean expression) that is true of acceptable behaviours and false of unacceptable behaviours. It follows that refinement is reversed implication universally quantified over behaviours:
Commands in a programming language are considered to be a special case of specifications—special only because they are compilable. For example in an environment where the program variables are
, 
, and 
, the command 
is considered equivalent to the predicate (represented here by a boolean expression)
in which
, 
, and 
represent the initial values of the program variables and 
, 
, and 
represent the final values of the program variables. Thus
Specification language
A specification language is a formal language used in computer science.Unlike most programming languages, which are directly executable formal languages used to implement a system, specification languages are used during systems analysis, requirements analysis and systems design.Specification...
and refinement. The central idea of predicative programming is that each specification is a predicate (generally written as a boolean expression) that is true of acceptable behaviours and false of unacceptable behaviours. It follows that refinement is reversed implication universally quantified over behaviours:
Commands in a programming language are considered to be a special case of specifications—special only because they are compilable. For example in an environment where the program variables are
, , and , the command is considered equivalent to the predicate (represented here by a boolean expression)in which
, , and represent the initial values of the program variables and , , and represent the final values of the program variables. ThusExternal links
- http://www.cs.toronto.edu/~hehner/publist.htmlPublications by Eric HehnerEric HehnerEric C. R. Hehner, called Rick, is a Canadian computer scientist.Eric Hehner was born on 16 September 1947 in Ottawa. He studied mathematics and physics at Carleton University, obtaining his first degree in 1969. He gained a PhD in computer science from the University of Toronto in 1974. He then...
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