Compiling functional pipe/stream abstractions into conventional programs: Software Pipelines

Representing a potentially infinite indexed collection of data is a handy abstraction in a number of programming situations. Computational scientists routinely try to finess this notion by allocating an array of some “large enough” size, and (in a perhaps delicate move) re-allocate if it is not large enough. Even if one is aware of some direct implementation of infinite stream/pipe programming one might still dismiss it as one of those tricks promoted primarily by programming language theorists using Lisp or other oddball languages. In fact, the manipulation programs we discuss are most conveniently expressed in a functional representation, and are given in ANSI Common Lisp, but we use them to generate programs in C. Thus the stream/pipe abstraction may be used, in principle, even by those for whom all “real” programs must be written in some efficiently compiled language like C (or with minor changes, Fortran, etc.) The program applications include power series, sparse floating-point arithmetic, solution of ODEs.