An array-oriented (APL) wish list: ideas I think may be useful

ABSTRACT

The fundamental, data structure in APL is the array. Arrays are, in most APL dialects, the only data structure, from scalars as arrays with no dimensions to the complex structures of nested arrays. But there are other ways in which array concepts could be applied, yet so far they have not. These are the top items on my "Array-Oriented Wish List".Less fundamental---but far easier to implement---should be certain operators and functions I propose, which I think would enhance the power of existing array operations. Some of these already exist in one or more dialects of APL, and I think all would benefit if they were universally adopted.In this suite of proposals, some are general, others more specific, and some could interact with each other in positive synergy, but none of them requires any of the others to be useful. In some cases, I suggest potential variants, each reasonable in its own right.The purpose of this paper is to present the concepts. In most cases, I don't attempt to go into details of implementation. That would require a much more extensive treatment of each concept. I hope that others---especially implementers---might take up the challenge.

REFERENCES

• 1: Robert Bernecky, Function arrays, ACM SIGAPL APL Quote Quad, v.14 n.4, p.53-56, June 1984
• 2: Robert Bernecky , Roger K. W. Hui, Gerunds and representations, Proceedings of the international conference on APL '91, p.39-46, August 04-08, 1991, Palo Alto, California, United States
• 3: James A. Brown, Function assignment and arrays of functions, Proceedings of the international conference on APL, p.81-84, June 11-15, 1984, Finland
• 4: Jim Lucas, Array oriented exception handling: a proposal for dealing with “invalid” data, Proceedings of the international conference on APL: APL and the future, p.1-4, May 12-16, 1985, Seattle, Washington, United States
• 5: Lucas, Jim, "When Standard 'Datatypes' Aren't Enough", APL-uutiset 2/2000 (APL News 2/2000, publication of FinnAPL, Helsinki, Finland).

INDEX TERMS

Primary Classification:
  D. Software
  D.3 PROGRAMMING LANGUAGES
      D.3.2 Language Classifications

          Nouns: APL

Additional Classification:
  E. Data
  E.1 DATA STRUCTURES
      Subjects: Arrays

  F. Theory of Computation
  F.3 LOGICS AND MEANINGS OF PROGRAMS
      F.3.3 Studies of Program Constructs

General Terms:
Algorithms, Languages