diff options
| -rw-r--r-- | changelog.md | 3 | ||||
| -rw-r--r-- | compiler/vmops.nim | 6 | ||||
| -rw-r--r-- | lib/pure/math.nim | 27 | ||||
| -rw-r--r-- | tests/stdlib/tmath.nim | 10 |
4 files changed, 45 insertions, 1 deletions
diff --git a/changelog.md b/changelog.md index 306cf54d3..4e9b8c162 100644 --- a/changelog.md +++ b/changelog.md @@ -93,6 +93,9 @@ with other backends. see #9125. Use `-d:nimLegacyJsRound` for previous behavior. + +- Added `math.signbit`. + ## Language changes - `nimscript` now handles `except Exception as e`. diff --git a/compiler/vmops.nim b/compiler/vmops.nim index 3e859d3d7..504a352b5 100644 --- a/compiler/vmops.nim +++ b/compiler/vmops.nim @@ -16,6 +16,9 @@ from math import sqrt, ln, log10, log2, exp, round, arccos, arcsin, when declared(math.copySign): from math import copySign +when declared(math.signbit): + from math import signbit + from os import getEnv, existsEnv, dirExists, fileExists, putEnv, walkDir, getAppFilename from md5 import getMD5 from sighashes import symBodyDigest @@ -174,6 +177,9 @@ proc registerAdditionalOps*(c: PCtx) = when declared(copySign): wrap2f_math(copySign) + when declared(signbit): + wrap1f_math(signbit) + wrap1s(getMD5, md5op) proc `mod Wrapper`(a: VmArgs) {.nimcall.} = diff --git a/lib/pure/math.nim b/lib/pure/math.nim index a6a3676b9..bcda68afe 100644 --- a/lib/pure/math.nim +++ b/lib/pure/math.nim @@ -56,7 +56,7 @@ import std/private/since {.push debugger: off.} # the user does not want to trace a part # of the standard library! -import bitops, fenv +import std/[bitops, fenv] when defined(c) or defined(cpp): proc c_isnan(x: float): bool {.importc: "isnan", header: "<math.h>".} @@ -65,6 +65,8 @@ when defined(c) or defined(cpp): proc c_copysign(x, y: cfloat): cfloat {.importc: "copysignf", header: "<math.h>".} proc c_copysign(x, y: cdouble): cdouble {.importc: "copysign", header: "<math.h>".} + proc c_signbit(x: SomeFloat): cint {.importc: "signbit", header: "<math.h>".} + func binom*(n, k: int): int = ## Computes the `binomial coefficient <https://en.wikipedia.org/wiki/Binomial_coefficient>`_. runnableExamples: @@ -156,6 +158,29 @@ func isNaN*(x: SomeFloat): bool {.inline, since: (1,5,1).} = when defined(js): fn() else: result = c_isnan(x) +when defined(js): + proc toBitsImpl(x: float): array[2, uint32] = + asm """ + const buffer = new ArrayBuffer(8); + const floatBuffer = new Float64Array(buffer); + const uintBuffer = new Uint32Array(buffer); + floatBuffer[0] = `x`; + `result` = uintBuffer + """ + +proc signbit*(x: SomeFloat): bool {.inline, since: (1, 5, 1).} = + ## Returns true if `x` is negative, false otherwise. + runnableExamples: + doAssert not signbit(0.0) + doAssert signbit(-0.0) + doAssert signbit(-0.1) + doAssert not signbit(0.1) + when defined(js): + let uintBuffer = toBitsImpl(x) + result = (uintBuffer[1] shr 31) != 0 + else: + result = c_signbit(x) != 0 + func copySign*[T: SomeFloat](x, y: T): T {.inline, since: (1, 5, 1).} = ## Returns a value with the magnitude of `x` and the sign of `y`; ## this works even if x or y are NaN or zero, both of which can carry a sign. diff --git a/tests/stdlib/tmath.nim b/tests/stdlib/tmath.nim index e5cb58eba..62fdcd19f 100644 --- a/tests/stdlib/tmath.nim +++ b/tests/stdlib/tmath.nim @@ -304,6 +304,16 @@ block: template main = # xxx wrap all under `main` so it also gets tested in vm. + block: # signbit + doAssert not signbit(0.0) + doAssert signbit(-0.0) + doAssert signbit(-0.1) + doAssert not signbit(0.1) + + doAssert not signbit(Inf) + doAssert signbit(-Inf) + doAssert not signbit(NaN) + block: # isNaN doAssert NaN.isNaN doAssert not Inf.isNaN |