Joined
·
1,650 Posts
Does anyone know scheme decently well? This is what I need to do:
Write a procedure free-vars that takes a list structure representing an expression in the lambda calculus syntax and returns a set (a list without duplicates) of all the variables that occur free in the expression.
I have the boolean occurs-free? but I seriously have no idea how to even start going about this!
Thanks in advance for any help I receive.
Write a procedure free-vars that takes a list structure representing an expression in the lambda calculus syntax and returns a set (a list without duplicates) of all the variables that occur free in the expression.
I have the boolean occurs-free? but I seriously have no idea how to even start going about this!

Thanks in advance for any help I receive.