prometheus/pkg/value/value.go

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// Copyright 2016 The Prometheus Authors
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package value
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import (
"math"
)
const (
// NormalNaN is a quiet NaN. This is also math.NaN().
NormalNaN uint64 = 0x7ff8000000000001
// StaleNaN is a signalling NaN, due to the MSB of the mantissa being 0.
// This value is chosen with many leading 0s, so we have scope to store more
// complicated values in the future. It is 2 rather than 1 to make
// it easier to distinguish from the NormalNaN by a human when debugging.
StaleNaN uint64 = 0x7ff0000000000002
)
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// IsStaleNaN returns true when the provided NaN value is a stale marker.
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func IsStaleNaN(v float64) bool {
return math.Float64bits(v) == StaleNaN
}