* Added table/types.ToDecimal() converter from table/types.Value to table/types.Decimal

Author: asmyasnikov

CHANGELOG.md

@@ -1,5 +1,7 @@
+* Added `table/types.ToDecimal()` converter from `table/types.Value` to `table/types.Decimal`
+
 ## v3.46.1
-* Implemented `xcontext.With{Cancel,Timeout}` with stack record and switched all usages from standard `context.With{Cancel,Timeout}`
+* Implemented `internal/xcontext.With{Cancel,Timeout}` with stack record and switched all usages from standard `context.With{Cancel,Timeout}`
 
 ## v3.46.0
 * Refactored package `log` for support typed fields in log messages

internal/value/value.go

@@ -410,11 +410,31 @@ func DatetimeValueFromTime(t time.Time) datetimeValue {
 	return datetimeValue(t.Unix())
 }
 
+var _ DecimalValuer = (*decimalValue)(nil)
+
 type decimalValue struct {
 	value     [16]byte
 	innerType *DecimalType
 }
 
+func (v *decimalValue) Value() [16]byte {
+	return v.value
+}
+
+func (v *decimalValue) Precision() uint32 {
+	return v.innerType.Precision
+}
+
+func (v *decimalValue) Scale() uint32 {
+	return v.innerType.Scale
+}
+
+type DecimalValuer interface {
+	Value() [16]byte
+	Precision() uint32
+	Scale() uint32
+}
+
 func (v *decimalValue) castTo(dst interface{}) error {
 	return xerrors.WithStackTrace(fmt.Errorf("cannot cast '%+v' to '%T' destination", v, dst))
 }

table/types/cast.go

@@ -18,6 +18,17 @@ func CastTo(v Value, dst interface{}) error {
 	return value.CastTo(v, dst)
 }
 
+func ToDecimal(v Value) (*Decimal, error) {
+	if valuer, isDecimalValuer := v.(value.DecimalValuer); isDecimalValuer {
+		return &Decimal{
+			Bytes:     valuer.Value(),
+			Precision: valuer.Precision(),
+			Scale:     valuer.Scale(),
+		}, nil
+	}
+	return nil, xerrors.WithStackTrace(fmt.Errorf("value type '%s' is not decimal type", v.Type().Yql()))
+}
+
 func TupleItems(v Value) ([]Value, error) {
 	if vv, has := v.(interface {
 		Items() []Value