APL trivia

ABSTRACT

APL derives great expressive power from seemingly trivial features, such as empty arrays, but there is still resistance to the implementation of the elementary trivial functions including left/stop ⊣ and right/pass ⊢, which perform no calculations. This paper defines functional triviality; describes trivial functions and operators and their uses; discusses the mathematical basis of their expressive power; and defines new trivial functions and operators. It urges implementation of several of these functions as primitives for reasons of efficiency and expressiveness, and considers their efficient implementation via idiom recognition.

REFERENCES

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INDEX TERMS

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

          Nouns: APL

Additional Classification:
  D. Software
  D.3 PROGRAMMING LANGUAGES
      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:
Design, Languages, Theory