Lambda Calculus Meta-variables Supported in my Newlisp Library.

Lambda calculus is very small and still "Turing complete" language. However, because of its simplicity and small size, it is very hard to write real programs - even harder than in assembly language. Most of the materials demonstrating programming in lambda calculus> use meta-variables. For instance, TRUE is defined as

'(^ x .(^ y . x))),

and after that, TRUE is used instead of given expression. If such meta-variables are used, lambda-expressions are much shorter and more readable, however, there is no essential difference, since before reduction, all meta-variables are "expanded" into real lambda-expressions.

I already implemented support for reduction of lambda expressions in my Newlisp library. The code that deals with meta-variables is rather simple. It is  just recursive substitution of meta-variable's value for meta-variable itself.

You can see how it works in my previous post, now updated.

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