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(let <bindings> <body>)syntax

Syntax: <Bindings> should have the form

((<variable[1]> <init[1]>) ...),

where each <init> is an expression, and <body> should be a sequence of one or more expressions. It is an error for a <variable> to appear more than once in the list of variables being bound.

Semantics: The <init>s are evaluated in the current environment (in some unspecified order), the <variable>s are bound to fresh locations holding the results, the <body> is evaluated in the extended environment, and the value(s) of the last expression of <body> is(are) returned. Each binding of a <variable> has <body> as its region.

(let ((x 2) (y 3))
  (* x y))                              ===>  6

(let ((x 2) (y 3))
  (let ((x 7)
        (z (+ x y)))
    (* z x)))                           ===>  35

See also "named let", below.