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:.
template dollarImpl(x: uint | uint64, result: var string) =
type destTyp = typeof(x)
if x == 0:
result = "0"
else:
result = newString(60)
var i = 0
var n = x
while n != 0:
let nn = n div destTyp(10)
result[i] = char(n - destTyp(10) * 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])
when defined(js):
import std/private/since
since (1, 3):
proc `$`*(x: uint): string =
## Caveat: currently implemented as $(cast[int](x)), tied to current
## semantics of js' Number type.
# for c, see strmantle.`$`
when nimvm:
dollarImpl(x, result)
else:
result = $(int(x))
proc `$`*(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
when nimvm:
dollarImpl(x, result)
else:
result = $(cast[int](x))
else:
proc `$`*(x: uint64): string {.noSideEffect, raises: [].} =
## The stringify operator for an unsigned integer argument. Returns `x`
## converted to a decimal string.
dollarImpl(x, result)
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, "[", ", ", "]")