pre { line-height: 125%; }
td.linenos .normal { color: inherit; background-color: transparent; padding-left: 5px; padding-right: 5px; }
span.linenos { color: inherit; background-color: transparent; padding-left: 5px; padding-right: 5px; }
td.linenos .special { color: #000000; background-color: #ffffc0; padding-left: 5px; padding-right: 5px; }
span.linenos.special { color: #000000; background-color: #ffffc0; padding-left: 5px; padding-right: 5px; }
.highlight .hll { background-color: #ffffcc }
.highlight .c { color: #888888 } /* Comment */
.highlight .err { color: #a61717; background-color: #e3d2d2 } /* Error */
.highlight .k { color: #008800; font-weight: bold } /* Keyword */
.highlight .ch { color: #888888 } /* Comment.Hashbang */
.highlight .cm { color: #888888 } /* Comment.Multiline */
.highlight .cp { color: #cc0000; font-weight: bold } /* Comment.Preproc */
.highlight .cpf { color: #888888 } /* Comment.PreprocFile */
.highlight .c1 { color: #888888 } /* Comment.Single */
.highlight .cs { color: #cc0000; font-weight: bold; background-color: #fff0f0 } /* Comment.Special */
.highlight .gd { color: #000000; background-color: #ffdddd } /* Generic.Deleted */
.highlight .ge { font-style: italic } /* Generic.Emph */
.highlight .ges { font-weight: bold; font-style: italic } /* Generic.EmphStrong */
.highlight .gr { color: #aa0000 } /* Generic.Error */
.highlight .gh { color: #333333 } /* Generic.Heading */
.highlight .gi { color: #000000; background-color: #ddffdd } /* Generic.Inserted */
.highlight .go { color: #888888 } /* Generic.Output */
.highlight .gp { color: #555555 } /* Generic.Prompt */
.highlight .gs { font-weight: bold } /* Generic.Strong */
.highlight .gu { color: #666666 } /* Generic.Subheading */
.highlight .gt { color: #aa0000 } /* Generic.Traceback */
.highlight .kc { color: #008800; font-weight: bold } /* Keyword.Constant */
.highlight .kd { color: #008800; font-weight: bold } /* Keyword.Declaration */
.highlight .kn { color: #008800; font-weight: bold } /* Keyword.Namespace */
.highlight .kp { color: #008800 } /* Keyword.Pseudo */
.highlight .kr { color: #008800; font-weight: bold } /* Keyword.Reserved */
.highlight .kt { color: #888888; font-weight: bold } /* Keyword.Type */
.highlight .m { color: #0000DD; font-weight: bold } /* Literal.Number */
.highlight .s { color: #dd2200; background-color: #fff0f0 } /* Literal.String */
.highlight .na { color: #336699 } /* Name.Attribute */
.highlight .nb { color: #003388 } /* Name.Builtin */
.highlight .nc { color: #bb0066; font-weight: bold } /* Name.Class */
.highlight .no { color: #003366; font-weight: bold } /* Name.Constant */
.highlight .nd { color: #555555 } /* Name.Decorator */
.highlight .ne { color: #bb0066; font-weight: bold } /* Name.Exception */
.highlight .nf { color: #0066bb; font-weight: bold } /* Name.Function */
.highlight .nl { color: #336699; font-style: italic } /* Name.Label */
.highlight .nn { color: #bb0066; font-weight: bold } /* Name.Namespace */
.highlight .py { color: #336699; font-weight: bold } /* Name.Property */
.highlight .nt { color: #bb0066; font-weight: bold } /* Name.Tag */
.highlight .nv { color: #336699 } /* Name.Variable */
.highlight .ow { color: #008800 } /* Operator.Word */
.highlight .w { color: #bbbbbb } /* Text.Whitespace */
.highlight .mb { color: #0000DD; font-weight: bold } /* Literal.Number.Bin */
.highlight .mf { color: #0000DD; font-weight: bold } /* Literal.Number.Float */
.highlight .mh { color: #0000DD; font-weight: bold } /* Literal.Number.Hex */
.highlight .mi { color: #0000DD; font-weight: bold } /* Literal.Number.Integer */
.highlight .mo { color: #0000DD; font-weight: bold } /* Literal.Number.Oct */
.highlight .sa { color: #dd2200; background-color: #fff0f0 } /* Literal.String.Affix */
.highlight .sb { color: #dd2200; background-color: #fff0f0 } /* Literal.String.Backtick */
.highlight .sc { color: #dd2200; background-color: #fff0f0 } /* Literal.String.Char */
.highlight .dl { color: #dd2200; background-color: #fff0f0 } /* Literal.String.Delimiter */
.highlight .sd { color: #dd2200; background-color: #fff0f0 } /* Literal.String.Doc */
.highlight .s2 { color: #dd2200; background-color: #fff0f0 } /* Literal.String.Double */
.highlight .se { color: #0044dd; background-color: #fff0f0 } /* Literal.String.Escape */
.highlight .sh { color: #dd2200; background-color: #fff0f0 } /* Literal.String.Heredoc */
.highlight .si { color: #3333bb; background-color: #fff0f0 } /* Literal.String.Interpol */
.highlight .sx { color: #22bb22; background-color: #f0fff0 } /* Literal.String.Other */
.highlight .sr { color: #008800; background-color: #fff0ff } /* Literal.String.Regex */
.highlight .s1 { color: #dd2200; background-color: #fff0f0 } /* Literal.String.Single */
.highlight .ss { color: #aa6600; background-color: #fff0f0 } /* Literal.String.Symbol */
.highlight .bp { color: #003388 } /* Name.Builtin.Pseudo */
.highlight .fm { color: #0066bb; font-weight: bold } /* Name.Function.Magic */
.highlight .vc { color: #336699 } /* Name.Variable.Class */
.highlight .vg { color: #dd7700 } /* Name.Variable.Global */
.highlight .vi { color: #3333bb } /* Name.Variable.Instance */
.highlight .vm { color: #336699 } /* Name.Variable.Magic */
.highlight .il { color: #0000DD; font-weight: bold } /* Literal.Number.Integer.Long */
<p>Denne side hjælper til første-gangs installation og konfiguration af
<a href="http://dokuwiki.org">Dokuwiki</a>. Mere information om denne
installer er tilgængelig på dens egen
<a href="http://dokuwiki.org/installer">dokumentations side</a>.</p>

<p>DokuWiki bruger almindelige filer til at gemme wiki sider og anden
information relaterende til disse sider (f.eks. billeder, søge indeks, gamle
udgaver, osv).  For at fungerer optimalt <strong>skal</strong> DokuWiki have
skrive adgang til mapperne der holder disse filer. Denne installer er ikke
istand til at opsætte mappe tilladelser. Det skal normalt udføres direkte i en
kommando shell eller hvis du bruger hosting, gennem FTP eller dit hostings
kontrol panel (f.eks. cPanel).</p>

<p>Denne installer vil opsætte din DokuWiki konfiguration for
<abbr title="access control list">ACL</abbr>, hvilket tillader
administrator login og adgang til DokuWiki's adminstrative menu til
installation af udvidelser, håndtering af brugere, håndtering af adgang til wiki
sider og ændring af konfigurations indstillinger. Det er ikke et krav for at
DokuWiki kan fungere, men det vil gøre DokuWiki lettere at administre.</p>

<p>Erfarne brugere og brugere med specielle opsætningskrav burde bruge disse
henvisninger for detaljer vedrørende
<a href="http://dokuwiki.org/install">installations instruktioner</a>
og <a href="http://dokuwiki.org/config">konfigurations indstillinger</a>.</p>

#
#
#            Nim's Runtime Library
#        (c) Copyright 2012 Andreas Rumpf
#
#    See the file "copying.txt", included in this
#    distribution, for details about the copyright.
#

## The `packedsets` module implements an efficient `Ordinal` set implemented as a
## `sparse bit set`:idx:.
##
## Supports any Ordinal type.
##
## **Note**: Currently the assignment operator `=` for `PackedSet[A]`
## performs some rather meaningless shallow copy. Since Nim currently does
## not allow the assignment operator to be overloaded, use the `assign proc
## <#assign,PackedSet[A],PackedSet[A]>`_ to get a deep copy.
##
## See also
## ========
## * `sets module <sets.html>`_ for more general hash sets

import std/private/since
import hashes

type
  BitScalar = uint

const
  InitIntSetSize = 8              # must be a power of two!
  TrunkShift = 9
  BitsPerTrunk = 1 shl TrunkShift # needs to be a power of 2 and
                                  # divisible by 64
  TrunkMask = BitsPerTrunk - 1
  IntsPerTrunk = BitsPerTrunk div (sizeof(BitScalar) * 8)
  IntShift = 5 + ord(sizeof(BitScalar) == 8) # 5 or 6, depending on int width
  IntMask = 1 shl IntShift - 1

type
  Trunk = ref object
    next: Trunk                                 # all nodes are connected with this pointer
    key: int                                    # start address at bit 0
    bits: array[0..IntsPerTrunk - 1, BitScalar] # a bit vector

  TrunkSeq = seq[Trunk]

  PackedSet*[A: Ordinal] = object
    ## An efficient set of `Ordinal` types implemented as a sparse bit set.
    elems: int           # only valid for small numbers
    counter, max: int
    head: Trunk
    data: TrunkSeq
    a: array[0..33, int] # profiling shows that 34 elements are enough

proc mustRehash[T](t: T): bool {.inline.} =
  let length = t.max + 1
  assert length > t.counter
  result = (length * 2 < t.counter * 3) or (length - t.counter < 4)

proc nextTry(h, maxHash: Hash, perturb: var Hash): Hash {.inline.} =
  const PERTURB_SHIFT = 5
  var perturb2 = cast[uint](perturb) shr PERTURB_SHIFT
  perturb = cast[Hash](perturb2)
  result = ((5 * h) + 1 + perturb) and maxHash

proc packedSetGet[A](t: PackedSet[A], key: int): Trunk =
  var h = key and t.max
  var perturb = key
  while t.data[h] != nil:
    if t.data[h].key == key:
      return t.data[h]
    h = nextTry(h, t.max, perturb)
  result = nil

proc intSetRawInsert[A](t: PackedSet[A], data: var TrunkSeq, desc: Trunk) =
  var h = desc.key and t.max
  var perturb = desc.key
  while data[h] != nil:
    assert data[h] != desc
    h = nextTry(h, t.max, perturb)
  assert data[h] == nil
  data[h] = desc

proc intSetEnlarge[A](t: var PackedSet[A]) =
  var n: TrunkSeq
  var oldMax = t.max
  t.max = ((t.max + 1) * 2) - 1
  newSeq(n, t.max + 1)
  for i in countup(0, oldMax):
    if t.data[i] != nil: intSetRawInsert(t, n, t.data[i])
  swap(t.data, n)

proc intSetPut[A](t: var PackedSet[A], key: int): Trunk =
  var h = key and t.max
  var perturb = key
  while t.data[h] != nil:
    if t.data[h].key == key:
      return t.data[h]
    h = nextTry(h, t.max, perturb)
  if mustRehash(t): intSetEnlarge(t)
  inc(t.counter)
  h = key and t.max
  perturb = key
  while t.data[h] != nil: h = nextTry(h, t.max, perturb)
  assert t.data[h] == nil
  new(result)
  result.next = t.head
  result.key = key
  t.head = result
  t.data[h] = result

proc bitincl[A](s: var PackedSet[A], key: int) {.inline.} =
  var ret: Trunk
  var t = intSetPut(s, key shr TrunkShift)
  var u = key and TrunkMask
  t.bits[u shr IntShift] = t.bits[u shr IntShift] or
      (BitScalar(1) shl (u and IntMask))

proc exclImpl[A](s: var PackedSet[A], key: int) =
  if s.elems <= s.a.len:
    for i in 0..<s.elems:
      if s.a[i] == key:
        s.a[i] = s.a[s.elems - 1]
        dec(s.elems)
        return
  else:
    var t = packedSetGet(s, key shr TrunkShift)
    if t != nil:
      var u = key and TrunkMask
      t.bits[u shr IntShift] = t.bits[u shr IntShift] and
          not(BitScalar(1) shl (u and IntMask))

template dollarImpl(): untyped =
  result = "{"
  for key in items(s):
    if result.len > 1: result.add(", ")
    result.add $key
  result.add("}")

iterator items*[A](s: PackedSet[A]): A {.inline.} =
  ## Iterates over any included element of `s`.
  if s.elems <= s.a.len:
    for i in 0..<s.elems:
      yield A(s.a[i])
  else:
    var r = s.head
    while r != nil:
      var i = 0
      while i <= high(r.bits):
        var w: uint = r.bits[i]
        # taking a copy of r.bits[i] here is correct, because
        # modifying operations are not allowed during traversation
        var j = 0
        while w != 0: # test all remaining bits for zero
          if (w and 1) != 0: # the bit is set!
            yield A((r.key shl TrunkShift) or (i shl IntShift +% j))
          inc(j)
          w = w shr 1
        inc(i)
      r = r.next

proc initPackedSet*[A]: PackedSet[A] =
  ## Returns an empty `PackedSet[A]`.
  ## `A` must be `Ordinal`.
  ##
  ## **See also:**
  ## * `toPackedSet proc <#toPackedSet,openArray[A]>`_
  runnableExamples:
    let a = initPackedSet[int]()
    assert len(a) == 0

    type Id = distinct int
    var ids = initPackedSet[Id]()
    ids.incl(3.Id)

  result = PackedSet[A](
    elems: 0,
    counter: 0,
    max: 0,
    head: nil,
    data: @[])
  #  a: array[0..33, int] # profiling shows that 34 elements are enough

proc contains*[A](s: PackedSet[A], key: A): bool =
  ## Returns true if `key` is in `s`.
  ##
  ## This allows the usage of the `in` operator.
  runnableExamples:
    type ABCD = enum A, B, C, D

    let a = [1, 3, 5].toPackedSet
    assert a.contains(3)
    assert 3 in a
    assert not a.contains(8)
    assert 8 notin a

    let letters = [A, C].toPackedSet
    assert A in letters
    assert C in letters
    assert B notin letters

  if s.elems <= s.a.len:
    for i in 0..<s.elems:
      if s.a[i] == ord(key): return true
  else:
    var t = packedSetGet(s, ord(key) shr TrunkShift)
    if t != nil:
      var u = ord(key) and TrunkMask
      result = (t.bits[u shr IntShift] and
                (BitScalar(1) shl (u and IntMask))) != 0
    else:
      result = false

proc incl*[A](s: var PackedSet[A], key: A) =
  ## Includes an element `key` in `s`.
  ##
  ## This doesn't do anything if `key` is already in `s`.
  ##
  ## **See also:**
  ## * `excl proc <#excl,PackedSet[A],A>`_ for excluding an element
  ## * `incl proc <#incl,PackedSet[A],PackedSet[A]>`_ for including a set
  ## * `containsOrIncl proc <#containsOrIncl,PackedSet[A],A>`_
  runnableExamples:
    var a = initPackedSet[int]()
    a.incl(3)
    a.incl(3)
    assert len(a) == 1

  if s.elems <= s.a.len:
    for i in 0..<s.elems:
      if s.a[i] == ord(key): return
    if s.elems < s.a.len:
      s.a[s.elems] = ord(key)
      inc(s.elems)
      return
    newSeq(s.data, InitIntSetSize)
    s.max = InitIntSetSize - 1
    for i in 0..<s.elems:
      bitincl(s, s.a[i])
    s.elems = s.a.len + 1
    # fall through:
  bitincl(s, ord(key))

proc incl*[A](s: var PackedSet[A], other: PackedSet[A]) =
  ## Includes all elements from `other` into `s`.
  ##
  ## This is the in-place version of `s + other <#+,PackedSet[A],PackedSet[A]>`_.
  ##
  ## **See also:**
  ## * `excl proc <#excl,PackedSet[A],PackedSet[A]>`_ for excluding a set
  ## * `incl proc <#incl,PackedSet[A],A>`_ for including an element
  ## * `containsOrIncl proc <#containsOrIncl,PackedSet[A],A>`_
  runnableExamples:
    var a = [1].toPackedSet
    a.incl([5].toPackedSet)
    assert len(a) == 2
    assert 5 in a

  for item in other.items: incl(s, item)

proc toPackedSet*[A](x: openArray[A]): PackedSet[A] {.since: (1, 3).} =
  ## Creates a new `PackedSet[A]` that contains the elements of `x`.
  ##
  ## Duplicates are removed.
  ##
  ## **See also:**
  ## * `initPackedSet proc <#initPackedSet>`_
  runnableExamples:
    let a = [5, 6, 7, 8, 8].toPackedSet
    assert len(a) == 4
    assert $a == "{5, 6, 7, 8}"

  result = initPackedSet[A]()
  for item in x:
    result.incl(item)

proc containsOrIncl*[A](s: var PackedSet[A], key: A): bool =
  ## Includes `key` in the set `s` and tells if `key` was already in `s`.
  ##
  ## The difference with regards to the `incl proc <#incl,PackedSet[A],A>`_ is
  ## that this proc returns true if `s` already contained `key`. The
  ## proc will return false if `key` was added as a new value to `s` during
  ## this call.
  ##
  ## **See also:**
  ## * `incl proc <#incl,PackedSet[A],A>`_ for including an element
  ## * `missingOrExcl proc <#missingOrExcl,PackedSet[A],A>`_
  runnableExamples:
    var a = initPackedSet[int]()
    assert a.containsOrIncl(3) == false
    assert a.containsOrIncl(3) == true
    assert a.containsOrIncl(4) == false

  if s.elems <= s.a.len:
    for i in 0..<s.elems:
      if s.a[i] == ord(key):
        return true
    incl(s, key)
    result = false
  else:
    var t = packedSetGet(s, ord(key) shr TrunkShift)
    if t != nil:
      var u = ord(key) and TrunkMask
      result = (t.bits[u shr IntShift] and BitScalar(1) shl (u and IntMask)) != 0
      if not result:
        t.bits[u shr IntShift] = t.bits[u shr IntShift] or
            (BitScalar(1) shl (u and IntMask))
    else:
      incl(s, key)
      result = false

proc excl*[A](s: var PackedSet[A], key: A) =
  ## Excludes `key` from the set `s`.
  ##
  ## This doesn't do anything if `key` is not found in `s`.
  ##
  ## **See also:**
  ## * `incl proc <#incl,PackedSet[A],A>`_ for including an element
  ## * `excl proc <#excl,PackedSet[A],PackedSet[A]>`_ for excluding a set
  ## * `missingOrExcl proc <#missingOrExcl,PackedSet[A],A>`_
  runnableExamples:
    var a = [3].toPackedSet
    a.excl(3)
    a.excl(3)
    a.excl(99)
    assert len(a) == 0

  exclImpl[A](s, ord(key))

proc excl*[A](s: var PackedSet[A], other: PackedSet[A]) =
  ## Excludes all elements from `other` from `s`.
  ##
  ## This is the in-place version of `s - other <#-,PackedSet[A],PackedSet[A]>`_.
  ##
  ## **See also:**
  ## * `incl proc <#incl,PackedSet[A],PackedSet[A]>`_ for including a set
  ## * `excl proc <#excl,PackedSet[A],A>`_ for excluding an element
  ## * `missingOrExcl proc <#missingOrExcl,PackedSet[A],A>`_
  runnableExamples:
    var a = [1, 5].toPackedSet
    a.excl([5].toPackedSet)
    assert len(a) == 1
    assert 5 notin a

  for item in other.items:
    excl(s, item)

proc len*[A](s: PackedSet[A]): int {.inline.} =
  ## Returns the number of elements in `s`.
  runnableExamples:
    let a = [1, 3, 5].toPackedSet
    assert len(a) == 3

  if s.elems < s.a.len:
    result = s.elems
  else:
    result = 0
    for _ in s.items:
      # pending bug #11167; when fixed, check each explicit `items` to see if it can be removed
      inc(result)

proc missingOrExcl*[A](s: var PackedSet[A], key: A): bool =
  ## Excludes `key` from the set `s` and tells if `key` was already missing from `s`.
  ##
  ## The difference with regards to the `excl proc <#excl,PackedSet[A],A>`_ is
  ## that this proc returns true if `key` was missing from `s`.
  ## The proc will return false if `key` was in `s` and it was removed
  ## during this call.
  ##
  ## **See also:**
  ## * `excl proc <#excl,PackedSet[A],A>`_ for excluding an element
  ## * `excl proc <#excl,PackedSet[A],PackedSet[A]>`_ for excluding a set
  ## * `containsOrIncl proc <#containsOrIncl,PackedSet[A],A>`_
  runnableExamples:
    var a = [5].toPackedSet
    assert a.missingOrExcl(5) == false
    assert a.missingOrExcl(5) == true

  var count = s.len
  exclImpl(s, ord(key))
  result = count == s.len

proc clear*[A](result: var PackedSet[A]) =
  ## Clears the `PackedSet[A]` back to an empty state.
  runnableExamples:
    var a = [5, 7].toPackedSet
    clear(a)
    assert len(a) == 0

  # setLen(result.data, InitIntSetSize)
  # for i in 0..InitIntSetSize - 1: result.data[i] = nil
  # result.max = InitIntSetSize - 1
  result.data = @[]
  result.max = 0
  result.counter = 0
  result.head = nil
  result.elems = 0

proc isNil*[A](x: PackedSet[A]): bool {.inline.} =
  ## Returns true if `x` is empty, false otherwise.
  runnableExamples:
    var a = initPackedSet[int]()
    assert a.isNil
    a.incl(2)
    assert not a.isNil
    a.excl(2)
    assert a.isNil

  x.head.isNil and x.elems == 0

proc assign*[A](dest: var PackedSet[A], src: PackedSet[A]) =
  ## Copies `src` to `dest`.
  ## `dest` does not need to be initialized by the `initPackedSet proc <#initPackedSet>`_.
  runnableExamples:
    var
      a = initPackedSet[int]()
      b = initPackedSet[int]()
    b.incl(5)
    b.incl(7)
    a.assign(b)
    assert len(a) == 2

  if src.elems <= src.a.len:
    dest.data = @[]
    dest.max = 0
    dest.counter = src.counter
    dest.head = nil
    dest.elems = src.elems
    dest.a = src.a
  else:
    dest.counter = src.counter
    dest.max = src.max
    dest.elems = src.elems
    newSeq(dest.data, src.data.len)

    var it = src.head
    while it != nil:
      var h = it.key and dest.max
      var perturb = it.key
      while dest.data[h] != nil: h = nextTry(h, dest.max, perturb)
      assert dest.data[h] == nil
      var n: Trunk
      new(n)
      n.next = dest.head
      n.key = it.key
      n.bits = it.bits
      dest.head = n
      dest.data[h] = n
      it = it.next

proc union*[A](s1, s2: PackedSet[A]): PackedSet[A] =
  ## Returns the union of the sets `s1` and `s2`.
  ##
  ## The same as `s1 + s2 <#+,PackedSet[A],PackedSet[A]>`_.
  runnableExamples:
    let
      a = [1, 2, 3].toPackedSet
      b = [3, 4, 5].toPackedSet
      c = union(a, b)
    assert c.len == 5
    assert c == [1, 2, 3, 4, 5].toPackedSet

  result.assign(s1)
  incl(result, s2)

proc intersection*[A](s1, s2: PackedSet[A]): PackedSet[A] =
  ## Returns the intersection of the sets `s1` and `s2`.
  ##
  ## The same as `s1 * s2 <#*,PackedSet[A],PackedSet[A]>`_.
  runnableExamples:
    let
      a = [1, 2, 3].toPackedSet
      b = [3, 4, 5].toPackedSet
      c = intersection(a, b)
    assert c.len == 1
    assert c == [3].toPackedSet

  result = initPackedSet[A]()
  for item in s1.items:
    if contains(s2, item):
      incl(result, item)

proc difference*[A](s1, s2: PackedSet[A]): PackedSet[A] =
  ## Returns the difference of the sets `s1` and `s2`.
  ##
  ## The same as `s1 - s2 <#-,PackedSet[A],PackedSet[A]>`_.
  runnableExamples:
    let
      a = [1, 2, 3].toPackedSet
      b = [3, 4, 5].toPackedSet
      c = difference(a, b)
    assert c.len == 2
    assert c == [1, 2].toPackedSet

  result = initPackedSet[A]()
  for item in s1.items:
    if not contains(s2, item):
      incl(result, item)

proc symmetricDifference*[A](s1, s2: PackedSet[A]): PackedSet[A] =
  ## Returns the symmetric difference of the sets `s1` and `s2`.
  runnableExamples:
    let
      a = [1, 2, 3].toPackedSet
      b = [3, 4, 5].toPackedSet
      c = symmetricDifference(a, b)
    assert c.len == 4
    assert c == [1, 2, 4, 5].toPackedSet

  result.assign(s1)
  for item in s2.items:
    if containsOrIncl(result, item):
      excl(result, item)

proc `+`*[A](s1, s2: PackedSet[A]): PackedSet[A] {.inline.} =
  ## Alias for `union(s1, s2) <#union,PackedSet[A],PackedSet[A]>`_.
  result = union(s1, s2)

proc `*`*[A](s1, s2: PackedSet[A]): PackedSet[A] {.inline.} =
  ## Alias for `intersection(s1, s2) <#intersection,PackedSet[A],PackedSet[A]>`_.
  result = intersection(s1, s2)

proc `-`*[A](s1, s2: PackedSet[A]): PackedSet[A] {.inline.} =
  ## Alias for `difference(s1, s2) <#difference,PackedSet[A],PackedSet[A]>`_.
  result = difference(s1, s2)

proc disjoint*[A](s1, s2: PackedSet[A]): bool =
  ## Returns true if the sets `s1` and `s2` have no items in common.
  runnableExamples:
    let
      a = [1, 2].toPackedSet
      b = [2, 3].toPackedSet
      c = [3, 4].toPackedSet
    assert disjoint(a, b) == false
    assert disjoint(a, c) == true

  for item in s1.items:
    if contains(s2, item):
      return false
  return true

proc card*[A](s: PackedSet[A]): int {.inline.} =
  ## Alias for `len() <#len,PackedSet[A]>`_.
  ##
  ## Card stands for the [cardinality](http://en.wikipedia.org/wiki/Cardinality)
  ## of a set.
  result = s.len()

proc `<=`*[A](s1, s2: PackedSet[A]): bool =
  ## Returns true if `s1` is a subset of `s2`.
  ##
  ## A subset `s1` has all of its elements in `s2`, but `s2` doesn't necessarily
  ## have more elements than `s1`. That is, `s1` can be equal to `s2`.
  runnableExamples:
    let
      a = [1].toPackedSet
      b = [1, 2].toPackedSet
      c = [1, 3].toPackedSet
    assert a <= b
    assert b <= b
    assert not (c <= b)

  for item in s1.items:
    if not s2.contains(item):
      return false
  return true

proc `<`*[A](s1, s2: PackedSet[A]): bool =
  ## Returns true if `s1` is a proper subset of `s2`.
  ##
  ## A strict or proper subset `s1` has all of its elements in `s2`, but `s2` has
  ## more elements than `s1`.
  runnableExamples:
    let
      a = [1].toPackedSet
      b = [1, 2].toPackedSet
      c = [1, 3].toPackedSet
    assert a < b
    assert not (b < b)
    assert not (c < b)

  return s1 <= s2 and not (s2 <= s1)

proc `==`*[A](s1, s2: PackedSet[A]): bool =
  ## Returns true if both `s1` and `s2` have the same elements and set size.
  runnableExamples:
    assert [1, 2].toPackedSet == [2, 1].toPackedSet
    assert [1, 2].toPackedSet == [2, 1, 2].toPackedSet

  return s1 <= s2 and s2 <= s1

proc `$`*[A](s: PackedSet[A]): string =
  ## Converts `s` to a string.
  runnableExamples:
    let a = [1, 2, 3].toPackedSet
    assert $a == "{1, 2, 3}"

  dollarImpl()