A survey of extensions to APL

  title={A survey of extensions to APL},
  author={K.F. Ruehr},
  booktitle={APL '82},
  • K.F. Ruehr
  • Published in APL '82 26 July 1982
  • Mathematics
A survey of proposed extensions to the APL language is made with emphasis placed on the motivations for various proposals, the differences between them and the consequences of their adoption. Some issues of a more general nature concerning the purpose, process and direction of language extension are also discussed. An extensive bibliography is provided with annotations concerning the nature, development and influence of various authors' works. Areas of extension encompassed by the survey… 

An Array and List Processing System

It is shown how using their common features as design principles, the mathematical power of APL and the flexibility of LISP are combined into a simple yet effective tool for diverse system engineering tasks.

The integration of relational database algebra into APL

The aim of the project described here is to strengthen APL as a Fourth Generation Language by widening its scope though the addition of some database facilities, specifically data manipulation primitives.

Arrays and references

An analysis of both nested and boxed array systems, in the light of a new development in APL which consists of the introduction of anew data-type in the language, shows the interest of having both systems with their own specificities.

Empty Arrays in Extended APL

  • D. Orth
  • Computer Science
    IBM J. Res. Dev.
  • 1984
In this paper various possibilities for providing consistent behavior are presented and the new proposals possess at least one of two important qualities in which older proposals tend to be deficient.

JMSL - a language derived from APL

A new AFL-derived language called JMSL is presented which rnodifies seven aspects of APL so that many current and poten tial APL users could benefit from a language which is easier to learn, read,

Examples of event handling in APL2

  • A. Graham
  • Business, Computer Science
    APL '83
  • 1983
The examples given show some novel uses that may not be obvious on first introduction to @@@@EA (Execute Alternate) which may be used on any APL system with sufficiently powerful event handling.

From trees into boxes

This work is part of a larger effort to provide a comprehensive set of facilities in J for working with tree structures, and exemplifies the way in which one can tailor the J interpreter to special needs.

APL teaching bugs

By facing issues inherent in the teaching of APL that confront the instructor with difficult choices, teachers may make APL more comprehensible and hence foster its acceptance and growth.

Indexing and merging in APL

Mathematically, an array may be usefully viewed as a function, in this particular case, as a function of its indices. A proposal is made for an operator which derives such a function for its array

Brackets are a PL's best friend

It is pointed out again that brackets have more virtues than vices, that they represent a valuable notational convenience that has not yet been fully exploited, and that they could well be exploited to stand for another component of APL on a par with functions and operators.



On the locus of program flow within and among secondary functions

This paper suggests restricting the forms, but not the power, of branching in APL, which provides an alternate view of suspended functions and permits branching to be generalized to include co-routines.

Some implications of APL order-of-execution rules

The refined “right to left” evaluation rule is examined and compared with other possible choices, through the use of simple APL syntax analysis models, to determine its implications on storage requirements, computation requirements, and mathematical identities.

Some implications of shared variables

Current APL systems, such as APLSV, embody two shared variable facilities: one for establishing temporary interfaces between system components, and the other one for defining parts of the permanent interface between an APL program and the underlying processor.

Parsing and evaluation of APL with operators

The difficulties that arise with the introduction of function valued and basic valued operators in APL are considered and various modifications to the syntactic and semantic structure of APL that serve to avoid these difficulties are discussed.

A programming language

  • K. Iverson
  • Computer Science
    AIEE-IRE '62 (Spring)
  • 1962
The paper describes a succinct problem-oriented programming language that relies heavily on a systematic extension of a small set of basic operations to vectors, matrices, and trees, and on a family of flexible selection operations controlled by logical vectors.

The role of operators in APL

Operators, which apply to functions to produce functions, are an important component of APL. Despite their importance, their role is not well understood, and they are often lumped with functions in

A development system for testing array theory concepts

An experimental programming system has been written in APL to allow exploration of array theory and its use in a programming environment. The system combines array theory notation with programming

APL\XAD: An extension of APL for abstract data manipulation

An extension to APL is presented which allows a very high level treatment of abstract data and a set-theoretic notation is introduced that allows concise but lucid handling of structural components and information content.

Improved security in APL applications packages

This paper describes an experimental augmentation of APL/360 which substantially improves the privacy and security of APL applications packages. It is based upon the concept of “qualifying” a name:

“Extension of APL to tree-structured information”

A new outlook on the APL system management together with a new set of primitive functions and symbols extensions needed to handle the new objects as well as the maintaining of a maximum coherence between these extensions and the standard APL operations are proposed.