A minisystem programming language

TRAIL is a block-structured language and programming system for the development of programming support systems and translators for problem-oriented languages on minicomputers. The programming system includes an interpreter for an intermediate language (IL) into which various source languages (including TRAIL itself) may be translated. The interpreter size is about 1400 bytes. The choice of an interpreted target language was guided by the objectives of minimum object code size and machine independence of the developed software. Both of these have been achieved, at the expense of a 20:1 slowdown of execution speed relative to directly assembled code. The interpreted object code is at least 50% smaller than assembly code. The source language was designed to match the requirements of language translator software; software design directly models syntax checking, context-free translation, and context-sensitive translation aspects, in ascending order of complexity. Anticipated benefits include greater productivity in design and debug phases, and enhanced communication between programmers via simplified documentation procedures.