CLU (programming language)

CLU is a programming language created at the Massachusetts Institute of Technology by Barbara Liskov and her students beginning in 1973, with the language first appearing in the mid 1970s. It organizes programs around classes with constructors and methods but deliberately omits inheritance, favoring class based data abstraction over a full object oriented model. CLU introduced or popularized a cluster of ideas that later became standard in programming language design, including abstract data types, iterators for controlling loops, call by sharing parameter passing, multiple return values from a single procedure call, and type safe parameterized and variant types. Although CLU itself saw limited practical use outside MIT, its influence on later object oriented and type safe languages is well documented.