(This won't work in Racket, because Racket doesn't even try to represent the internal structure of a function in a human-readable way.)
*Lambda terms*: lambda terms are written with a backslash, thus: `((\x (\y x)) z)`.
-If you click "Reduce", the system will produce a lambda term that is guaranteed to be reduction equivalent (`<~~>`) with the original term.
+If you click "Reduce", the system will produce a lambda term that is guaranteed to be reduction equivalent (`<~~>`) with the original term. So `((\x (\y x)) z)` reduces to (a lambda term equivalent to) `(\y z)`.
*Let*: in order to make building a more elaborate system easier, it is possible to define values using `let`.
In this toy system, `let`s should only be used at the beginning of a file. If we have, for intance,
let true = (\x (\y x)) in
let false = (\x (\y y)) in
+ ((true true) false)
+
+the result is `true`.
*Comments*: