A scheme for little languages in interactive graphics

Programming environments for interactive graphics software typically have a multiplicity of tools and applications. Many of these programs contain ad hoc ‘little language’ interpreters1 that do many similar things in needlessly different ways. In particular, many little languages have, in addition to their special‐purpose constructs, vestigial support for ordinary programming, such as variables, loops and conditionals. If a single, standard programming language were the basis for all these little languages, they could have complete, coherent programming semantics; they could communicate with each other more easily; no design work for basic constructs would be needed; and interpreter implementation work would be saved. The approach of reusing and extending the same core language and interpreter for a variety of little languages is the extension language approach.