Untying the Gordian knot: agreement in J

ABSTRACT

The “Dictionary of J” is not written for the faint of heart. Its numerous self-references make it very difficult to tackle. The author thinks that section II.B, “Verbs”, is one of the keys for getting a confident grip of the language. This paper basically just repeats this section using a tutorial style, some historical background, and several pictures. Hopefully, it will enable people with analytical minds to find their own way through the Dictionary. It closes with a discussion of possible language changes in the context of II.B

REFERENCES

• BENKA84.: J. Philip Benkard, Rank vs depth for array partitioning, ACM SIGAPL APL Quote Quad, v.14 n.4, p.33-39, June 1984
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• BROWN91.: James A. Brown, "TryAPL2 for free," IBM Corporation (August 1991). Introduction accompanying the demonstration product.
• BrCr91: J. A. Brown , H. P. Crowder, APL2: getting started, IBM Systems Journal, v.30 n.4, p.433-445, 1991
• EisPe93.: Murray Eisenberg , Howard A. Peelle, Confessions of two APL educators learning J, ACM SIGAPL APL Quote Quad, v.24 n.1, p.78-87, Aug. 1993
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INDEX TERMS

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

          Nouns: J

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

          Nouns: APL
      D.3.3 Language Constructs and Features
          Subjects: Procedures, functions, and subroutines

  F. Theory of Computation
  F.3 LOGICS AND MEANINGS OF PROGRAMS
      F.3.3 Studies of Program Constructs
          Subjects: Functional constructs

General Terms:
Algorithms, Languages

Keywords:
J, agreement, array processing, cells, execution model, rank