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@ -7,10 +7,20 @@
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(list? procedure? . -> . list?)
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(dropf-right (dropf items test-proc) test-proc))
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;; convert a list into a list of slices that are len long (last one might be shorter)
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(define+provide/contract (list->slices xs len)
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(list? integer? . -> . (listof list?))
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(cond
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[(equal? xs null) null]
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[(len . > . (length xs)) (list xs)]
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[else (cons (take xs len) (list->slices (drop xs len) len))]))
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;; split list into list of sublists using test-proc
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(define+provide/contract (splitf-at* xs split-test)
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;; todo: better error message when split-test is not a predicate
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(list? predicate/c . -> . (listof list?))
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(define (&splitf-at* xs [acc '()]) ; use acc for tail recursion
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