// NewGauge initializes a new Gauge, registers it with the "expvar" package and
// returns it. The initial value is NaN.
func NewGauge(id api.Identifier) *Gauge {
g := &Gauge{
id: id,
value: api.Gauge(math.NaN()),
}
Publish(g)
expvar.Publish(id.String(), g)
return g
}
// NewDerive initializes a new Derive, registers it with the "expvar" package
// and returns it. The initial value is zero.
func NewDerive(id api.Identifier) *Derive {
d := &Derive{
id: id,
value: 0,
}
Publish(d)
expvar.Publish(id.String(), d)
return d
}