llvm-project/llgo/third_party/gotools/go/exact/go13.go

25 lines
507 B
Go

// Copyright 2014 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// +build !go1.4
package exact
import (
"math"
"math/big"
)
func ratToFloat32(x *big.Rat) (float32, bool) {
// Before 1.4, there's no Rat.Float32.
// Emulate it, albeit at the cost of
// imprecision in corner cases.
x64, exact := x.Float64()
x32 := float32(x64)
if math.IsInf(float64(x32), 0) {
exact = false
}
return x32, exact
}