This calculator implements a normal-order evaluator for the untyped lambda-calculus with shortcuts. Shortcuts are distinguished constants that represent terms. An association between a shortcut symbol and a term must be declared before any term that contains the shortcut could be evaluated. The declaration of a shortcut does not cause the corresponding term to be evaluated. Therefore shortcut's term may contain other shortcuts -- or even yet to be defined ones. Shortcuts make programming in lambda-calculus remarkably more convenient.
Besides palying a bit with the LC, I suggest downloading and reading the code. Well commented, with quite useful comments if you are learning the lambda calculus.
Posted to LC by Ehud Lamm on 4/18/01; 3:59:32 AM