--Copyright (c) 1991-2002, The Numerical ALgorithms Group Ltd.
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)abbrev package SORTPAK SortPackage
++ Description:
++ This package exports sorting algorithnms
SortPackage(S,A) : Exports == Implementation where
  S: Type
  A: IndexedAggregate(Integer,S)
    with (finiteAggregate; shallowlyMutable)

  Exports == with
    bubbleSort!: (A,(S,S) -> Boolean) -> A
	++ bubbleSort!(a,f) \undocumented
    insertionSort!: (A, (S,S) -> Boolean) -> A
	++ insertionSort!(a,f) \undocumented
    if S has OrderedSet then
      bubbleSort!: A -> A
	++ bubbleSort!(a) \undocumented
      insertionSort!: A -> A
	++ insertionSort! \undocumented

  Implementation == add
    bubbleSort!(m,f) ==
      n := #m
      for i in 1..(n-1) repeat
        for j in n..(i+1) by -1 repeat
          if f(m.j,m.(j-1)) then swap!(m,j,j-1)
      m
    insertionSort!(m,f) ==
      for i in 2..#m repeat
        j := i
        while j > 1 and f(m.j,m.(j-1)) repeat
          swap!(m,j,j-1)
          j := (j - 1) pretend PositiveInteger
      m
    if S has OrderedSet then
      bubbleSort!(m) == bubbleSort!(m,_<$S)
      insertionSort!(m) == insertionSort!(m,_<$S)
    if A has UnaryRecursiveAggregate(S) then
      bubbleSort!(m,fn) ==
        empty? m => m
        l := m
        while not empty? (r := l.rest) repeat
           r := bubbleSort!(r,fn)
           x := l.first
           if fn(r.first,x) then
             l.first := r.first
             r.first := x
           l.rest := r
           l := l.rest
        m

