Restructuring of APL functions

Abstract

The philosophy and style that has come to be known as "structured programmlng" emphasizes great concern with the manner in which a program is organized [1]. It implies that some program constructions are more effective than others, even though both might yield identical results. In many software applications, human efficiency (which might be related to such things as the ability to read, alter and understand programs) is more important than computer efficiency (which includes less memory space and/or execution time).In APL, branching is generally used within a defined function to direct the execution of commands. It is denoted by the symbol → followed by an expression E: →E. Since the value of E, the expression to the right of the branch arrow, may be scalar or vector, the form the branch command takes is a function of the ability of the programmer. A suitable standard form for the branch command is desirable and feasible.For the purposes of this discussion, the "branch to specified line number or execute next line": form of the branch command is selected as the standard form. It is entirely feasible to perform branch standardization automatically and still preserve the meaning of the original function. This paper describes such an approach.