The type inference and coercion facilities in the scratchpad II interpreter

ABSTRACT

The Scratchpad II system is an abstract datatype programming language, a compiler for the language, a library of packages of polymorphic functions and parametrized abstract datatypes, and an interpreter that provides sophisticated type inference and coercion facilities. Although originally designed for the implementation of symbolic mathematical algorithms, Scratchpad II is a general purpose programming language. This paper discusses aspects of the implementation of the interpreter and how it attempts to provide a user friendly and relatively weakly typed front end for the strongly typed programming language.

REFERENCES

• 1: Richard D. Jenks , Barry M. Trager, A language for computational algebra, Proceedings of the fourth ACM symposium on Symbolic and algebraic computation, p.6-13, August 05-07, 1981, Snowbird, Utah, United States [doi>10.1145/800206.806363]
• 2: B Liskov , E Moss , A Snyder , R Atkinson , J C. Schaffert , T Bloom , R Scheifler, CLU reference manual, Springer-Verlag New York, Inc., New York, NY, 1984
• 3: [3] Computer Algebra Group. An Overview of the Scratchpad II Language and System, Yorktown Heights, New York: IBM Corporation, April 1986.
• 4: [4] Sweedler, Moss E., "Typing in Scratchpad II," The Scratchpad II Newsletter, Vol. 1, No. 2. Edited by R. S. Sutor, Yorktown Heights, New York: IBM Corporation, January 15, 1986.
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• 6: Craig Schaffert , Topher Cooper , Bruce Bullis , Mike Kilian , Carrie Wilpolt, An introduction to Trellis/Owl, ACM SIGPLAN Notices, v.21 n.11, p.9-16, Nov. 1986
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INDEX TERMS

Classification:
  D. Software
  D.3 PROGRAMMING LANGUAGES
      D.3.3 Language Constructs and Features
          Subjects: Abstract data types
      D.3.4 Processors
          Subjects: Interpreters

  I. Computing Methodologies
  I.1 SYMBOLIC AND ALGEBRAIC MANIPULATION
      I.1.3 Languages and Systems

          Nouns: SCRATCHPAD