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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 */
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.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
import std/private/since

proc `$`*(x: int): string {.magic: "IntToStr", noSideEffect.}
  ## The stringify operator for an integer argument. Returns `x`
  ## converted to a decimal string. ``$`` is Nim's general way of
  ## spelling `toString`:idx:.

when defined(js):
  since (1, 3):
    proc `$`*(x: uint): string =
      ## Caveat: currently implemented as $(cast[int](x)), tied to current
      ## semantics of js' Number type.
      # for c, see strmantle.`$`
      $(cast[int](x))

    proc `$`*(x: uint64): string =
      ## Compatibility note:
      ## the results may change in future releases if/when js target implements
      ## 64bit ints.
      # pending https://github.com/nim-lang/RFCs/issues/187
      $(cast[int](x))
else:
  proc `$`*(x: uint64): string {.noSideEffect, raises: [].} =
    ## The stringify operator for an unsigned integer argument. Returns `x`
    ## converted to a decimal string.
    if x == 0:
      result = "0"
    else:
      result = newString(60)
      var i = 0
      var n = x
      while n != 0:
        let nn = n div 10'u64
        result[i] = char(n - 10'u64 * nn + ord('0'))
        inc i
        n = nn
      result.setLen i

      let half = i div 2
      # Reverse
      for t in 0 .. half-1: swap(result[t], result[i-t-1])

proc `$`*(x: int64): string {.magic: "Int64ToStr", noSideEffect.}
  ## The stringify operator for an integer argument. Returns `x`
  ## converted to a decimal string.

proc `$`*(x: float): string {.magic: "FloatToStr", noSideEffect.}
  ## The stringify operator for a float argument. Returns `x`
  ## converted to a decimal string.

proc `$`*(x: bool): string {.magic: "BoolToStr", noSideEffect.}
  ## The stringify operator for a boolean argument. Returns `x`
  ## converted to the string "false" or "true".

proc `$`*(x: char): string {.magic: "CharToStr", noSideEffect.}
  ## The stringify operator for a character argument. Returns `x`
  ## converted to a string.
  ##
  ## .. code-block:: Nim
  ##   assert $'c' == "c"

proc `$`*(x: cstring): string {.magic: "CStrToStr", noSideEffect.}
  ## The stringify operator for a CString argument. Returns `x`
  ## converted to a string.

proc `$`*(x: string): string {.magic: "StrToStr", noSideEffect.}
  ## The stringify operator for a string argument. Returns `x`
  ## as it is. This operator is useful for generic code, so
  ## that ``$expr`` also works if ``expr`` is already a string.

proc `$`*[Enum: enum](x: Enum): string {.magic: "EnumToStr", noSideEffect.}
  ## The stringify operator for an enumeration argument. This works for
  ## any enumeration type thanks to compiler magic.
  ##
  ## If a ``$`` operator for a concrete enumeration is provided, this is
  ## used instead. (In other words: *Overwriting* is possible.)

proc `$`*(t: typedesc): string {.magic: "TypeTrait".}
  ## Returns the name of the given type.
  ##
  ## For more procedures dealing with ``typedesc``, see
  ## `typetraits module <typetraits.html>`_.
  ##
  ## .. code-block:: Nim
  ##   doAssert $(typeof(42)) == "int"
  ##   doAssert $(typeof("Foo")) == "string"
  ##   static: doAssert $(typeof(@['A', 'B'])) == "seq[char]"

when defined(nimHasIsNamedTuple):
  proc isNamedTuple(T: typedesc): bool {.magic: "TypeTrait".}
else:
  # for bootstrap; remove after release 1.2
  proc isNamedTuple(T: typedesc): bool =
    # Taken from typetraits.
    when T isnot tuple: result = false
    else:
      var t: T
      for name, _ in t.fieldPairs:
        when name == "Field0":
          return compiles(t.Field0)
        else:
          return true
      return false


proc `$`*[T: tuple|object](x: T): string =
  ## Generic ``$`` operator for tuples that is lifted from the components
  ## of `x`. Example:
  ##
  ## .. code-block:: Nim
  ##   $(23, 45) == "(23, 45)"
  ##   $(a: 23, b: 45) == "(a: 23, b: 45)"
  ##   $() == "()"
  result = "("
  const isNamed = T is object or isNamedTuple(T)
  var count = 0
  for name, value in fieldPairs(x):
    if count > 0: result.add(", ")
    when isNamed:
      result.add(name)
      result.add(": ")
    count.inc
    when compiles($value):
      when value isnot string and value isnot seq and compiles(value.isNil):
        if value.isNil: result.add "nil"
        else: result.addQuoted(value)
      else:
        result.addQuoted(value)
    else:
      result.add("...")
  when not isNamed:
    if count == 1:
      result.add(",") # $(1,) should print as the semantically legal (1,)
  result.add(")")


proc collectionToString[T](x: T, prefix, separator, suffix: string): string =
  result = prefix
  var firstElement = true
  for value in items(x):
    if firstElement:
      firstElement = false
    else:
      result.add(separator)

    when value isnot string and value isnot seq and compiles(value.isNil):
      # this branch should not be necessary
      if value.isNil:
        result.add "nil"
      else:
        result.addQuoted(value)
    else:
      result.addQuoted(value)
  result.add(suffix)

proc `$`*[T](x: set[T]): string =
  ## Generic ``$`` operator for sets that is lifted from the components
  ## of `x`. Example:
  ##
  ## .. code-block:: Nim
  ##   ${23, 45} == "{23, 45}"
  collectionToString(x, "{", ", ", "}")

proc `$`*[T](x: seq[T]): string =
  ## Generic ``$`` operator for seqs that is lifted from the components
  ## of `x`. Example:
  ##
  ## .. code-block:: Nim
  ##   $(@[23, 45]) == "@[23, 45]"
  collectionToString(x, "@[", ", ", "]")

proc `$`*[T, U](x: HSlice[T, U]): string =
  ## Generic ``$`` operator for slices that is lifted from the components
  ## of `x`. Example:
  ##
  ## .. code-block:: Nim
  ##  $(1 .. 5) == "1 .. 5"
  result = $x.a
  result.add(" .. ")
  result.add($x.b)


when not defined(nimNoArrayToString):
  proc `$`*[T, IDX](x: array[IDX, T]): string =
    ## Generic ``$`` operator for arrays that is lifted from the components.
    collectionToString(x, "[", ", ", "]")

proc `$`*[T](x: openArray[T]): string =
  ## Generic ``$`` operator for openarrays that is lifted from the components
  ## of `x`. Example:
  ##
  ## .. code-block:: Nim
  ##   $(@[23, 45].toOpenArray(0, 1)) == "[23, 45]"
  collectionToString(x, "[", ", ", "]")