Formatted programming languages

Abstract

Abstract This paper presents a systematic approach to formatted language design that incorporates formatting within the syntax of programming languages. The approach includes: a metasyntax to ensure that program text is foldable, not only to avoid right margin overflow but also to preclude constructs which are visually confusing or ambiguous; a set of guidelines for language designers to enhance readability within the constraints of the metasyntax; and a folding algorithm which selectively folds a program text. The resulting automatic formatting is consistent with current practice in program and text layout. The effect of this approach is to put program format decisions in the domain of the language's designer, rather than its several implementors or numerous users, which implies uniformly formatted programs of improved readability and therefore usability.