Accession Number:

ADA086504

Title:

Building Program Models Incrementally from Informal Descriptions.

Descriptive Note:

Technical rept.,

Corporate Author:

STANFORD UNIV CA DEPT OF COMPUTER SCIENCE

Personal Author(s):

Report Date:

1979-10-01

Pagination or Media Count:

144.0

Abstract:

Program acquisition is the transformation of a program specification into an executable, but not necessarily efficient, program that meets the given specification. This thesis presents a solution to one aspect of the program acquisition problem the incremental construction of program models from informal descriptions. The key to the solution is a framework for incremental program acquisition that includes a formal language for expressing program fragments that contain informalities a control structure for the incremental recognition and assimilation of such fragments and a knowledge base of rules for acquiring programs specified with informalities. The thesis describes a LISP based computer system called the Program Model Builder PMB, which receives informal program fragments incrementally and assembles them into a very high level program model that is complete, semantically consistent, unambiguous, and executable. The program specification comes in the form of partial program fragments that arrive in any order and may exhibit such informalities as inconsistencies and ambiguous references. Possible sources of fragments are a natural language parser or a parser for a surface form of the fragments. PMB produces a program model that is a complete and executable computer program. the program fragment language used for specifications is a superset of the language in which program models are built. This program modelling language is a very high level programming language for symbolic processing that deals with such information structures as sets and mappings. The recognition paradigm used by PMB is a form of subgoaling that allows the parts of the program to be specified in an order chosen by the user, rather than dictated by the system.

Subject Categories:

  • Computer Programming and Software
  • Computer Hardware

Distribution Statement:

APPROVED FOR PUBLIC RELEASE