Get whatever is on the left, and then fully parenthesize it.

So there's a bunch of stuff, then there's

your operator, plus, then there's a bunch of stuff.

And so whatever stuff ended up in here, which is probably also parenthesized,

shows up and you get an appropriate, fully parenthesized expression.

And then eval, is again going to be a

big switch that also is going to work recursively.

So here's eval. And you can see in this particular case

that I've done it for three binary

ops, and these examples can be extended. So, if you have an interest in this,

you can readily extend this to the more a much fuller expression,

evaluation scheme for C++. And

notice, here's your critical, if you want to think of it as your recursion.