diff --git a/feature_iter_int.go b/feature_iter_int.go
index 6137348..4781c63 100644
--- a/feature_iter_int.go
+++ b/feature_iter_int.go
@@ -113,13 +113,9 @@ func (iter *Iterator) ReadUint32() (ret uint32) {
 }
 
 func (iter *Iterator) readUint32(c byte) (ret uint32) {
-	defer func() {
-		if iter.head < len(iter.buf) && iter.buf[iter.head] == '.' {
-			iter.ReportError("readUint32", "can not decode float as int")
-		}
-	}()
 	ind := intDigits[c]
 	if ind == 0 {
+		iter.assertInteger()
 		return 0 // single zero
 	}
 	if ind == invalidCharForNumber {
@@ -132,12 +128,14 @@ func (iter *Iterator) readUint32(c byte) (ret uint32) {
 		ind2 := intDigits[iter.buf[i]]
 		if ind2 == invalidCharForNumber {
 			iter.head = i
+			iter.assertInteger()
 			return value
 		}
 		i++
 		ind3 := intDigits[iter.buf[i]]
 		if ind3 == invalidCharForNumber {
 			iter.head = i
+			iter.assertInteger()
 			return value*10 + uint32(ind2)
 		}
 		//iter.head = i + 1
@@ -146,30 +144,35 @@ func (iter *Iterator) readUint32(c byte) (ret uint32) {
 		ind4 := intDigits[iter.buf[i]]
 		if ind4 == invalidCharForNumber {
 			iter.head = i
+			iter.assertInteger()
 			return value*100 + uint32(ind2)*10 + uint32(ind3)
 		}
 		i++
 		ind5 := intDigits[iter.buf[i]]
 		if ind5 == invalidCharForNumber {
 			iter.head = i
+			iter.assertInteger()
 			return value*1000 + uint32(ind2)*100 + uint32(ind3)*10 + uint32(ind4)
 		}
 		i++
 		ind6 := intDigits[iter.buf[i]]
 		if ind6 == invalidCharForNumber {
 			iter.head = i
+			iter.assertInteger()
 			return value*10000 + uint32(ind2)*1000 + uint32(ind3)*100 + uint32(ind4)*10 + uint32(ind5)
 		}
 		i++
 		ind7 := intDigits[iter.buf[i]]
 		if ind7 == invalidCharForNumber {
 			iter.head = i
+			iter.assertInteger()
 			return value*100000 + uint32(ind2)*10000 + uint32(ind3)*1000 + uint32(ind4)*100 + uint32(ind5)*10 + uint32(ind6)
 		}
 		i++
 		ind8 := intDigits[iter.buf[i]]
 		if ind8 == invalidCharForNumber {
 			iter.head = i
+			iter.assertInteger()
 			return value*1000000 + uint32(ind2)*100000 + uint32(ind3)*10000 + uint32(ind4)*1000 + uint32(ind5)*100 + uint32(ind6)*10 + uint32(ind7)
 		}
 		i++
@@ -177,6 +180,7 @@ func (iter *Iterator) readUint32(c byte) (ret uint32) {
 		value = value*10000000 + uint32(ind2)*1000000 + uint32(ind3)*100000 + uint32(ind4)*10000 + uint32(ind5)*1000 + uint32(ind6)*100 + uint32(ind7)*10 + uint32(ind8)
 		iter.head = i
 		if ind9 == invalidCharForNumber {
+			iter.assertInteger()
 			return value
 		}
 	}
@@ -185,6 +189,7 @@ func (iter *Iterator) readUint32(c byte) (ret uint32) {
 			ind = intDigits[iter.buf[i]]
 			if ind == invalidCharForNumber {
 				iter.head = i
+				iter.assertInteger()
 				return value
 			}
 			if value > uint32SafeToMultiply10 {
@@ -199,6 +204,7 @@ func (iter *Iterator) readUint32(c byte) (ret uint32) {
 			value = (value << 3) + (value << 1) + uint32(ind)
 		}
 		if !iter.loadMore() {
+			iter.assertInteger()
 			return value
 		}
 	}
@@ -229,13 +235,9 @@ func (iter *Iterator) ReadUint64() uint64 {
 }
 
 func (iter *Iterator) readUint64(c byte) (ret uint64) {
-	defer func() {
-		if iter.head < len(iter.buf) && iter.buf[iter.head] == '.' {
-			iter.ReportError("readUint64", "can not decode float as int")
-		}
-	}()
 	ind := intDigits[c]
 	if ind == 0 {
+		iter.assertInteger()
 		return 0 // single zero
 	}
 	if ind == invalidCharForNumber {
@@ -243,11 +245,73 @@ func (iter *Iterator) readUint64(c byte) (ret uint64) {
 		return
 	}
 	value := uint64(ind)
+	if iter.tail-iter.head > 10 {
+		i := iter.head
+		ind2 := intDigits[iter.buf[i]]
+		if ind2 == invalidCharForNumber {
+			iter.head = i
+			iter.assertInteger()
+			return value
+		}
+		i++
+		ind3 := intDigits[iter.buf[i]]
+		if ind3 == invalidCharForNumber {
+			iter.head = i
+			iter.assertInteger()
+			return value*10 + uint64(ind2)
+		}
+		//iter.head = i + 1
+		//value = value * 100 + uint32(ind2) * 10 + uint32(ind3)
+		i++
+		ind4 := intDigits[iter.buf[i]]
+		if ind4 == invalidCharForNumber {
+			iter.head = i
+			iter.assertInteger()
+			return value*100 + uint64(ind2)*10 + uint64(ind3)
+		}
+		i++
+		ind5 := intDigits[iter.buf[i]]
+		if ind5 == invalidCharForNumber {
+			iter.head = i
+			iter.assertInteger()
+			return value*1000 + uint64(ind2)*100 + uint64(ind3)*10 + uint64(ind4)
+		}
+		i++
+		ind6 := intDigits[iter.buf[i]]
+		if ind6 == invalidCharForNumber {
+			iter.head = i
+			iter.assertInteger()
+			return value*10000 + uint64(ind2)*1000 + uint64(ind3)*100 + uint64(ind4)*10 + uint64(ind5)
+		}
+		i++
+		ind7 := intDigits[iter.buf[i]]
+		if ind7 == invalidCharForNumber {
+			iter.head = i
+			iter.assertInteger()
+			return value*100000 + uint64(ind2)*10000 + uint64(ind3)*1000 + uint64(ind4)*100 + uint64(ind5)*10 + uint64(ind6)
+		}
+		i++
+		ind8 := intDigits[iter.buf[i]]
+		if ind8 == invalidCharForNumber {
+			iter.head = i
+			iter.assertInteger()
+			return value*1000000 + uint64(ind2)*100000 + uint64(ind3)*10000 + uint64(ind4)*1000 + uint64(ind5)*100 + uint64(ind6)*10 + uint64(ind7)
+		}
+		i++
+		ind9 := intDigits[iter.buf[i]]
+		value = value*10000000 + uint64(ind2)*1000000 + uint64(ind3)*100000 + uint64(ind4)*10000 + uint64(ind5)*1000 + uint64(ind6)*100 + uint64(ind7)*10 + uint64(ind8)
+		iter.head = i
+		if ind9 == invalidCharForNumber {
+			iter.assertInteger()
+			return value
+		}
+	}
 	for {
 		for i := iter.head; i < iter.tail; i++ {
 			ind = intDigits[iter.buf[i]]
 			if ind == invalidCharForNumber {
 				iter.head = i
+				iter.assertInteger()
 				return value
 			}
 			if value > uint64SafeToMultiple10 {
@@ -262,7 +326,14 @@ func (iter *Iterator) readUint64(c byte) (ret uint64) {
 			value = (value << 3) + (value << 1) + uint64(ind)
 		}
 		if !iter.loadMore() {
+			iter.assertInteger()
 			return value
 		}
 	}
 }
+
+func (iter *Iterator) assertInteger() {
+	if iter.head < len(iter.buf) && iter.buf[iter.head] == '.' {
+		iter.ReportError("assertInteger", "can not decode float as int")
+	}
+}