Scheme: When to use let, let*, and letrec? -


this question has answer here:

what difference between let, let*, , letrec?

please give thorough explanations , examples.

your best bet read official r5rs descriptions of let, let*, , letrec.

in short, however:

(let ((x 2))  (let ((x 3) (y x))   y) => 2  (let ((x 2))  (let* ((x 3) (y x))   y) => 3

so difference between let , let* let evaluate bindings respect level above (so doesn't matter order they're listed in) while let* sequentially. (let* ((x a) (b y))) equivalent (let ((x a)) (let ((b y))).

letrec, on other hand, allows bind recursive values. might write recursive function want within function scope , bind name using letrec.


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