diff options
Diffstat (limited to 'lib/std')
-rw-r--r-- | lib/std/jsbigints.nim | 193 |
1 files changed, 193 insertions, 0 deletions
diff --git a/lib/std/jsbigints.nim b/lib/std/jsbigints.nim new file mode 100644 index 000000000..733f3369b --- /dev/null +++ b/lib/std/jsbigints.nim @@ -0,0 +1,193 @@ +## Arbitrary precision integers. +## * https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/BigInt +when not defined(js): + {.fatal: "Module jsbigints is designed to be used with the JavaScript backend.".} + +type JsBigIntImpl {.importc: "bigint".} = int # https://github.com/nim-lang/Nim/pull/16606 +type JsBigInt* = distinct JsBigIntImpl ## Arbitrary precision integer for JavaScript target. + +func big*(integer: SomeInteger): JsBigInt {.importjs: "BigInt(#)".} = + ## Constructor for `JsBigInt`. + runnableExamples: + doAssert big(1234567890) == big"1234567890" + +func big*(integer: cstring): JsBigInt {.importjs: "BigInt(#)".} = + ## Constructor for `JsBigInt`. + runnableExamples: + doAssert big"-1" == big"1" - big"2" + +func toCstring*(this: JsBigInt; radix: 2..36): cstring {.importjs: "#.toString(#)".} = + ## Converts from `JsBigInt` to `cstring` representation. + ## * `radix` Base to use for representing numeric values. + ## https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/BigInt/toString + runnableExamples: + doAssert big"2147483647".toCstring(2) == "1111111111111111111111111111111".cstring + +func toCstring*(this: JsBigInt): cstring {.importjs: "#.toString()".} + ## Converts from `JsBigInt` to `cstring` representation. + ## https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/BigInt/toString + +func `$`*(this: JsBigInt): string = + ## Returns a `string` representation of `JsBigInt`. + runnableExamples: doAssert $big"1024" == "1024n" + $toCstring(this) & 'n' + +func wrapToInt*(this: JsBigInt; bits: Natural): JsBigInt {.importjs: + "(() => { const i = #, b = #; return BigInt.asIntN(b, i) })()".} = + ## Wraps `this` to a signed `JsBigInt` of `bits` bits in `-2 ^ (bits - 1)` .. `2 ^ (bits - 1) - 1`. + ## https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/BigInt/asIntN + runnableExamples: + doAssert (big("3") + big("2") ** big("66")).wrapToInt(13) == big("3") + +func wrapToUint*(this: JsBigInt; bits: Natural): JsBigInt {.importjs: + "(() => { const i = #, b = #; return BigInt.asUintN(b, i) })()".} = + ## Wraps `this` to an unsigned `JsBigInt` of `bits` bits in 0 .. `2 ^ bits - 1`. + ## https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/BigInt/asUintN + runnableExamples: + doAssert (big("3") + big("2") ** big("66")).wrapToUint(66) == big("3") + +func toNumber*(this: JsBigInt): BiggestInt {.importjs: "Number(#)".} = + ## Does not do any bounds check and may or may not return an inexact representation. + runnableExamples: + doAssert toNumber(big"2147483647") == 2147483647.BiggestInt + +func `+`*(x, y: JsBigInt): JsBigInt {.importjs: "(# $1 #)".} = + runnableExamples: + doAssert (big"9" + big"1") == big"10" + +func `-`*(x, y: JsBigInt): JsBigInt {.importjs: "(# $1 #)".} = + runnableExamples: + doAssert (big"9" - big"1") == big"8" + +func `*`*(x, y: JsBigInt): JsBigInt {.importjs: "(# $1 #)".} = + runnableExamples: + doAssert (big"42" * big"9") == big"378" + +func `div`*(x, y: JsBigInt): JsBigInt {.importjs: "(# / #)".} = + ## Same as `div` but for `JsBigInt`(uses JavaScript `BigInt() / BigInt()`). + runnableExamples: + doAssert big"13" div big"3" == big"4" + doAssert big"-13" div big"3" == big"-4" + doAssert big"13" div big"-3" == big"-4" + doAssert big"-13" div big"-3" == big"4" + +func `mod`*(x, y: JsBigInt): JsBigInt {.importjs: "(# % #)".} = + ## Same as `mod` but for `JsBigInt` (uses JavaScript `BigInt() % BigInt()`). + runnableExamples: + doAssert big"13" mod big"3" == big"1" + doAssert big"-13" mod big"3" == big"-1" + doAssert big"13" mod big"-3" == big"1" + doAssert big"-13" mod big"-3" == big"-1" + +func `<`*(x, y: JsBigInt): bool {.importjs: "(# $1 #)".} = + runnableExamples: + doAssert big"2" < big"9" + +func `<=`*(x, y: JsBigInt): bool {.importjs: "(# $1 #)".} = + runnableExamples: + doAssert big"1" <= big"5" + +func `==`*(x, y: JsBigInt): bool {.importjs: "(# == #)".} = + runnableExamples: + doAssert big"42" == big"42" + +func `**`*(x, y: JsBigInt): JsBigInt {.importjs: "((#) $1 #)".} = + runnableExamples: + doAssert (big"9" ** big"5") == big"59049" + +func `xor`*(x, y: JsBigInt): JsBigInt {.importjs: "(# ^ #)".} = + runnableExamples: + doAssert (big"555" xor big"2") == big"553" + +func `shl`*(a, b: JsBigInt): JsBigInt {.importjs: "(# << #)".} = + runnableExamples: + doAssert (big"999" shl big"2") == big"3996" + +func `shr`*(a, b: JsBigInt): JsBigInt {.importjs: "(# >> #)".} = + runnableExamples: + doAssert (big"999" shr big"2") == big"249" + +func `-`*(this: JsBigInt): JsBigInt {.importjs: "($1#)".} = + runnableExamples: + doAssert -(big"10101010101") == big"-10101010101" + +func inc*(this: var JsBigInt) {.importjs: "(++[#][0][0])".} = + runnableExamples: + var big1: JsBigInt = big"1" + inc big1 + doAssert big1 == big"2" + +func dec*(this: var JsBigInt) {.importjs: "(--[#][0][0])".} = + runnableExamples: + var big1: JsBigInt = big"2" + dec big1 + doAssert big1 == big"1" + +func inc*(this: var JsBigInt; amount: JsBigInt) {.importjs: "([#][0][0] += #)".} = + runnableExamples: + var big1: JsBigInt = big"1" + inc big1, big"2" + doAssert big1 == big"3" + +func dec*(this: var JsBigInt; amount: JsBigInt) {.importjs: "([#][0][0] -= #)".} = + runnableExamples: + var big1: JsBigInt = big"1" + dec big1, big"2" + doAssert big1 == big"-1" + +func `+=`*(x: var JsBigInt; y: JsBigInt) {.importjs: "([#][0][0] $1 #)".} = + runnableExamples: + var big1: JsBigInt = big"1" + big1 += big"2" + doAssert big1 == big"3" + +func `-=`*(x: var JsBigInt; y: JsBigInt) {.importjs: "([#][0][0] $1 #)".} = + runnableExamples: + var big1: JsBigInt = big"1" + big1 -= big"2" + doAssert big1 == big"-1" + +func `*=`*(x: var JsBigInt; y: JsBigInt) {.importjs: "([#][0][0] $1 #)".} = + runnableExamples: + var big1: JsBigInt = big"2" + big1 *= big"4" + doAssert big1 == big"8" + +func `/=`*(x: var JsBigInt; y: JsBigInt) {.importjs: "([#][0][0] $1 #)".} = + ## Same as `x = x div y`. + runnableExamples: + var big1: JsBigInt = big"11" + big1 /= big"2" + doAssert big1 == big"5" + +proc `+`*(_: JsBigInt): JsBigInt {.error: + "See https://github.com/tc39/proposal-bigint/blob/master/ADVANCED.md#dont-break-asmjs".} # Can not be used by design + ## **Do NOT use.** https://github.com/tc39/proposal-bigint/blob/master/ADVANCED.md#dont-break-asmjs + +proc low*(_: typedesc[JsBigInt]): JsBigInt {.error: + "Arbitrary precision integers do not have a known low.".} ## **Do NOT use.** + +proc high*(_: typedesc[JsBigInt]): JsBigInt {.error: + "Arbitrary precision integers do not have a known high.".} ## **Do NOT use.** + + +runnableExamples: + let big1: JsBigInt = big"2147483647" + let big2: JsBigInt = big"666" + doAssert JsBigInt isnot int + doAssert big1 != big2 + doAssert big1 > big2 + doAssert big1 >= big2 + doAssert big2 < big1 + doAssert big2 <= big1 + doAssert not(big1 == big2) + let z = JsBigInt.default + doAssert $z == "0n" + block: + var a: seq[JsBigInt] + a.setLen 2 + doAssert a == @[big"0", big"0"] + doAssert a[^1] == big"0" + var b: JsBigInt + doAssert b == big"0" + doAssert b == JsBigInt.default |