APL optimization: A unified approach

Since 1969, attempts have been made to improve the interpretation process of APL. These studies have merely resulted in simulations which do not allow definitive conclusions on their practical impact. The authors make a survey of these works, and compare the approaches by the light of semantic attributes, a very useful tool for understanding and describing the semantic of a language, and the possibilities of optimization. They are implementing a modular interpreter in order to make comparative evaluations.