russell@unturf.com
1326e8a106
- Peephole optimizer: eliminates VOID+POP pairs, JUMP-to-next-instruction. Adjusts jump targets after dead code removal. - --help/-h and --version/-v flags. - 4 example programs: fibonacci, generator, mergesort, objects. - README rewritten: documents bytecode compiler, --fast flag, all features. - 529 tests green.
27 lines
762 B
Text
27 lines
762 B
Text
;;; mergesort.lsp — functional merge sort
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;;; Run: python3 uncommonlisp.py --fast examples/mergesort.lsp
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(define (merge a b)
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(cond ((null? a) b)
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((null? b) a)
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((< (car a) (car b))
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(cons (car a) (merge (cdr a) b)))
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(else
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(cons (car b) (merge a (cdr b))))))
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(define (split lst)
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(let loop ((l lst) (a '()) (b '()))
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(if (null? l)
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(list a b)
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(loop (cdr l) b (cons (car l) a)))))
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(define (msort lst)
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(if (or (null? lst) (null? (cdr lst)))
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lst
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(let ((halves (split lst)))
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(merge (msort (car halves))
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(msort (cadr halves))))))
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(define data (reverse (iota 20)))
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(display "Input: ") (display data) (newline)
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(display "Sorted: ") (display (msort data)) (newline)
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