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# Named `let`
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A named `let` is an iteration and recursion form. It uses the same
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syntactic keyword `let` as for local binding, but an identifier after
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the `let` \(instead of an immediate open parenthesis\) triggers a
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different parsing.
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```racket
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(let proc-id ([arg-id init-expr] ...)
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body ...+)
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```
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A named `let` form is equivalent to
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```racket
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(letrec ([proc-id (lambda (arg-id ...)
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body ...+)])
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(proc-id init-expr ...))
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```
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That is, a named `let` binds a function identifier that is visible only
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in the function’s body, and it implicitly calls the function with the
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values of some initial expressions.
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Examples:
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```racket
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(define (duplicate pos lst)
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(let dup ([i 0]
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[lst lst])
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(cond
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[(= i pos) (cons (car lst) lst)]
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[else (cons (car lst) (dup (+ i 1) (cdr lst)))])))
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> (duplicate 1 (list "apple" "cheese burger!" "banana"))
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'("apple" "cheese burger!" "cheese burger!" "banana")
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```
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