Function Convert

types/conversion.go:96–479

Convert converts the value to given scalar type.

(from Val, toID TypeID)

// Convert converts the value to given scalar type.
func Convert(from Val, toID TypeID) (Val, error) {
	to := Val{Tid: toID}

	// sanity: we expect a value
	data, ok := from.Value.([]byte)
	if !ok {
		return to, errors.Errorf("invalid data to convert to %s", toID.Name())
	}

	fromID := from.Tid
	res := &to.Value

	// Convert from-type to to-type and store in the result interface.
	switch fromID {
	case BinaryID:
		{
			// Unmarshal from Binary to type interfaces.
			switch toID {
			case BinaryID:
				*res = data
			case StringID, DefaultID:
				// We never modify from Val, so this should be safe.
				*res = *(*string)(unsafe.Pointer(&data))
			case IntID:
				if len(data) < 8 {
					return to, errors.Errorf("invalid data for int64 %v", data)
				}
				*res = int64(binary.LittleEndian.Uint64(data))
			case FloatID:
				if len(data) < 8 {
					return to, errors.Errorf("invalid data for float %v", data)
				}
				i := binary.LittleEndian.Uint64(data)
				*res = math.Float64frombits(i)
			case BigFloatID:
				var b big.Float
				b.SetPrec(BigFloatPrecision)
				if err := b.UnmarshalText(data); err != nil {
					return to, err
				}
				*res = b
			case BoolID:
				if len(data) == 0 || data[0] == 0 {
					*res = false
					return to, nil
				} else if data[0] == 1 {
					*res = true
					return to, nil
				}
				return to, errors.Errorf("invalid value for bool %v", data[0])
			case DateTimeID:
				var t time.Time
				if err := t.UnmarshalBinary(data); err != nil {
					return to, err
				}
				*res = t
			case GeoID:
				w, err := wkb.Unmarshal(data)