Premium
Variable associations in SNOBOL4
Author(s) -
Hanson David R.
Publication year - 1976
Publication title -
software: practice and experience
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.437
H-Index - 70
eISSN - 1097-024X
pISSN - 0038-0644
DOI - 10.1002/spe.4380060210
Subject(s) - programmer , computer science , debugging , programming language , variable (mathematics) , tracing , value (mathematics) , function (biology) , mathematical analysis , mathematics , machine learning , evolutionary biology , biology
This paper describes a new facility in the SNOBOL4 programming language that provides the capability to associate the execution of a programmer‐defined function with the act of assigning a variable a value or retrieving the value of a variable. The facility, called programmer‐defined variable association, subsumes the existing built‐in associations used for input, output and value tracing and provides, at the source‐language level, the protection and datatype coercion mechanisms used in keywords. Several applications are described that illustrate the usefulness of this addition to the language. The facility is especially useful for program monitoring and debugging. The implementation of this facility and the effect of implementation techniques on programming language design are also discussed.