motiejus/zig
1
Fork 0
Code Releases Activity

std.math.divCeil: support comptime_int/float

Browse Source
This commit is contained in:
Kate Tsuyu
2020-08-29 00:21:17 -04:00
parent f577d12fbc
commit 933bfcff64
1 changed files with 26 additions and 8 deletions
Download Patch File Download Diff File Expand all files Collapse all files

34
lib/std/math.zig
View File

@@ -624,15 +624,21 @@ fn testDivFloor() void {
pub fn divCeil(comptime T: type, numerator: T, denominator: T) !T {
@setRuntimeSafety(false);
if (denominator == 0) return error.DivisionByZero;
if (@typeInfo(T) == .Float) return @ceil(numerator / denominator);
if (T.is_signed and numerator < 0 and denominator < 0) {
if (numerator == minInt(T) and denominator == -1)
return error.Overflow;
return @divFloor(numerator + 1, denominator) + 1;
const info = @typeInfo(T);
switch (info) {
.ComptimeFloat, .Float => return @ceil(numerator / denominator),
.ComptimeInt, .Int => {
if (numerator < 0 and denominator < 0) {
if (info == .Int and numerator == minInt(T) and denominator == -1)
return error.Overflow;
return @divFloor(numerator + 1, denominator) + 1;
}
if (numerator > 0 and denominator > 0)
return @divFloor(numerator - 1, denominator) + 1;
return @divTrunc(numerator, denominator);
},
else => @compileError("divCeil unsupported on " ++ @typeName(T)),
}
if (numerator > 0 and denominator > 0)
return @divFloor(numerator - 1, denominator) + 1;
return @divTrunc(numerator, denominator);
}
test "math.divCeil" {
@@ -654,6 +660,18 @@ fn testDivCeil() void {
testing.expect((divCeil(f32, -5.0, 3.0) catch unreachable) == -1.0);
testing.expect((divCeil(f32, 5.0, -3.0) catch unreachable) == -1.0);
testing.expect((divCeil(f32, -5.0, -3.0) catch unreachable) == 2.0);
testing.expect((divCeil(comptime_int, 23, 4) catch unreachable) == 6);
testing.expect((divCeil(comptime_int, -23, 4) catch unreachable) == -5);
testing.expect((divCeil(comptime_int, 23, -4) catch unreachable) == -5);
testing.expect((divCeil(comptime_int, -23, -4) catch unreachable) == 6);
testing.expectError(error.DivisionByZero, divCeil(comptime_int, 23, 0));
testing.expect((divCeil(comptime_float, 23.0, 4.0) catch unreachable) == 6.0);
testing.expect((divCeil(comptime_float, -23.0, 4.0) catch unreachable) == -5.0);
testing.expect((divCeil(comptime_float, 23.0, -4.0) catch unreachable) == -5.0);
testing.expect((divCeil(comptime_float, -23.0, -4.0) catch unreachable) == 6.0);
testing.expectError(error.DivisionByZero, divCeil(comptime_float, 23.0, 0.0));
}
pub fn divExact(comptime T: type, numerator: T, denominator: T) !T {