The Lambda calculus defines what a function is from a computational perspective. It's comprised of three things:
- Variables (x, y, z, and so on)
- A way of creating functions (with the "\" notation)
- A way to apply functions (substitution)
Everything else is defined in terms of encoding those three things.
In Chapter 7, Functional Parameters, we defined a function where f is the function name, x is the input value, and the result is the whole expression f(x):
If f(x) = x + 2, then we know that every time we input the value three, five will always be the output value. So, functions are like black boxes where we put values in and ...
