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loosen typing on `break-at`

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pull/3/head
Matthew Butterick 10 years ago
parent fbfa56f2eb
commit abfb18d938
1 changed files with 2 additions and 2 deletions
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4
typed/sugar/list.rkt
Unescape Escape View File

@ -151,9 +151,9 @@
(define/typed+provide (break-at xs bps) (define/typed+provide (break-at xs bps)
(All (A) ((Listof A) (U Index (Listof Index)) -> (Listof (Listof A)))) (All (A) ((Listof A) (U Nonnegative-Integer (Listof Nonnegative-Integer)) -> (Listof (Listof A))))
(let ([bps (if (list? bps) bps (list bps))]) ; coerce bps to list (let ([bps (if (list? bps) bps (list bps))]) ; coerce bps to list
(when (ormap (λ:([bp : Index]) (>= bp (length xs))) bps) (when (ormap (λ:([bp : Nonnegative-Integer]) (>= bp (length xs))) bps)
(error 'break-at (format "breakpoint in ~v is greater than or equal to input list length = ~a" bps (length xs)))) (error 'break-at (format "breakpoint in ~v is greater than or equal to input list length = ~a" bps (length xs))))
;; easier to do back to front, because then the list index for each item won't change during the recursion ;; easier to do back to front, because then the list index for each item won't change during the recursion
;; cons a zero onto bps (which may already start with zero) and then use that as the terminating condition ;; cons a zero onto bps (which may already start with zero) and then use that as the terminating condition

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