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File: 1411383373103.png (22.33 KB, 614x1023, 614:1023, 614px-Greek_lc_lamda_thin.….png)

 No.229

Noob question here :
In lisp, I understand let is only syntactic sugar for an underlying lambda expression. But what about let*?

 No.231

Probably syntactic sugar for layers of lambdas.

I don't know what the inner workings of it is, but it allows you to reference variables that are also defined in the let* statement.
eg:

(let* ((a 1) (b (* a 5)))
…)

 No.233

>>231
That makes sense.


(let* ((a 1) (b (* a 5)))
  (print b))


becomes



(let ((a 1))
  (let ((b (* a 5))
    (print b)))


becomes



(funcall (lambda (a)
            (funcall (lambda (b)
                       (print b))
                      (* a 5)))
          1)


Or something along those lines.
Though, I believe if it were scheme, you could remove "funcall" and just 'call' the result of lambda.

 No.248

>>233
You don't need funcall in Scheme, using the lambda expression as a function will work. Like this:
((lambda (x) (+ x 1)) 1)

This will evaluate to 2.

 No.251

>>248
Someone needs to either clean up Common Lisp, or beef up Scheme.

 No.261

What I'm personally more intrigued with is letrec. How would letrec be represented using lambda expressions?


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