Remove NewZeroNumber in favor of Number(0) (#255)

api/core/number.go

@@ -42,19 +42,6 @@ type Number uint64
 
 // - constructors
 
-// NewZeroNumber
-func NewZeroNumber(kind NumberKind) Number {
-	switch kind {
-	case Int64NumberKind:
-		return NewInt64Number(0)
-	case Float64NumberKind:
-		return NewFloat64Number(0.)
-	case Uint64NumberKind:
-		return NewUint64Number(0)
-	}
-	return Number(0)
-}
-
 // NewNumberFromRaw creates a new Number from a raw value.
 func NewNumberFromRaw(r uint64) Number {
 	return Number(r)

api/core/number_test.go

@@ -146,3 +146,14 @@ func TestNumber(t *testing.T) {
 		}
 	}
 }
+
+func TestNumberZero(t *testing.T) {
+	zero := Number(0)
+	zerof := NewFloat64Number(0)
+	zeroi := NewInt64Number(0)
+	zerou := NewUint64Number(0)
+
+	if zero != zerof || zero != zeroi || zero != zerou {
+		t.Errorf("Invalid zero representations")
+	}
+}

sdk/metric/aggregator/counter/counter.go

@@ -45,10 +45,7 @@ func (c *Aggregator) AsNumber() core.Number {
 
 // Collect checkpoints the current value (atomically) and exports it.
 func (c *Aggregator) Collect(ctx context.Context, rec export.MetricRecord, exp export.MetricBatcher) {
-	desc := rec.Descriptor()
-	kind := desc.NumberKind()
-	zero := core.NewZeroNumber(kind)
-	c.checkpoint = c.current.SwapNumberAtomic(zero)
+	c.checkpoint = c.current.SwapNumberAtomic(core.Number(0))
 
 	exp.Export(ctx, rec, c)
 }

sdk/metric/aggregator/maxsumcount/msc.go

@@ -60,19 +60,15 @@ func (c *Aggregator) Max() core.Number {
 
 // Collect saves the current value (atomically) and exports it.
 func (c *Aggregator) Collect(ctx context.Context, rec export.MetricRecord, exp export.MetricBatcher) {
-	desc := rec.Descriptor()
-	kind := desc.NumberKind()
-	zero := core.NewZeroNumber(kind)
-
 	// N.B. There is no atomic operation that can update all three
 	// values at once, so there are races between Update() and
 	// Collect().  Therefore, atomically swap fields independently,
 	// knowing that individually the three parts of this aggregation
 	// could be spread across multiple collections in rare cases.
 
 	c.save.count.SetUint64(c.live.count.SwapUint64Atomic(0))
-	c.save.sum = c.live.sum.SwapNumberAtomic(zero)
-	c.save.max = c.live.max.SwapNumberAtomic(zero)
+	c.save.sum = c.live.sum.SwapNumberAtomic(core.Number(0))
+	c.save.max = c.live.max.SwapNumberAtomic(core.Number(0))
 
 	exp.Export(ctx, rec, c)
 }