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#lang racket/base
(provide nest)
;; A form that makes it easy to combine many "right-drifting" nested
;; expressions into a single one, sort of like a generalized version of the `*'
;; from `let*' and similar forms.
(define-syntax nest
(syntax-rules ()
[(nest () body0 body ...)
(let () body0 body ...)]
;; this allows putting definitions in the body
[(nest ([form forms ...]) body0 body ...)
(form forms ... (let () body0 body ...))]
[(nest ([form forms ...] . more) body0 body ...)
(form forms ... (nest more body0 body ...))]))
;; using this instead will allow splicing body expressions in the last form
;; whatever it happens to be, which can be (ab)used in strange ways
#;
(define-syntax nest
(syntax-rules ()
[(nest () body ...)
(begin body ...)]
[(nest ([form forms ...]) body ...)
(form forms ... body ...)]
[(nest ([form forms ...] . more) body ...)
(form forms ... (nest more body ...))]))
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