int.go

package cast

import (
	"fmt"
	"strconv"
)

// ToInt64 casts an interface to an int64 type, discarding any errors.
func ToInt64(i interface{}) int64 {
	ret, _ := ToInt64E(i)
	return ret
}

// ToInt64E casts an interface to an int64 type.
func ToInt64E(i interface{}) (int64, error) {
	i = indirect(i)

	switch s := i.(type) {
	case int:
		return int64(s), nil
	case int64:
		return s, nil
	case int32:
		return int64(s), nil
	case int16:
		return int64(s), nil
	case int8:
		return int64(s), nil
	case uint:
		return int64(s), nil
	case uint64:
		return int64(s), nil
	case uint32:
		return int64(s), nil
	case uint16:
		return int64(s), nil
	case uint8:
		return int64(s), nil
	case float64:
		return int64(s), nil
	case float32:
		return int64(s), nil
	case string:
		v, err := strconv.ParseInt(s, 0, 0)
		if err == nil {
			return v, nil
		}
		return 0, fmt.Errorf("unable to cast %#v of type %T to int64", i, i)
	case bool:
		if s {
			return 1, nil
		}
		return 0, nil
	case nil:
		return 0, nil
	default:
		return 0, fmt.Errorf("unable to cast %#v of type %T to int64", i, i)
	}
}

// ToInt32 casts an interface to an int32 type, discarding any errors.
func ToInt32(i interface{}) int32 {
	ret, _ := ToInt32E(i)
	return ret
}

// ToInt32E casts an interface to an int32 type.
func ToInt32E(i interface{}) (int32, error) {
	i = indirect(i)

	switch s := i.(type) {
	case int:
		return int32(s), nil
	case int64:
		return int32(s), nil
	case int32:
		return s, nil
	case int16:
		return int32(s), nil
	case int8:
		return int32(s), nil
	case uint:
		return int32(s), nil
	case uint64:
		return int32(s), nil
	case uint32:
		return int32(s), nil
	case uint16:
		return int32(s), nil
	case uint8:
		return int32(s), nil
	case float64:
		return int32(s), nil
	case float32:
		return int32(s), nil
	case string:
		v, err := strconv.ParseInt(s, 0, 0)
		if err == nil {
			return int32(v), nil
		}
		return 0, fmt.Errorf("unable to cast %#v of type %T to int32", i, i)
	case bool:
		if s {
			return 1, nil
		}
		return 0, nil
	case nil:
		return 0, nil
	default:
		return 0, fmt.Errorf("unable to cast %#v of type %T to int32", i, i)
	}
}

// ToInt16 casts an interface to an int16 type, discarding any errors.
func ToInt16(i interface{}) int16 {
	ret, _ := ToInt16E(i)
	return ret
}

// ToInt16E casts an interface to an int16 type.
func ToInt16E(i interface{}) (int16, error) {
	i = indirect(i)

	switch s := i.(type) {
	case int:
		return int16(s), nil
	case int64:
		return int16(s), nil
	case int32:
		return int16(s), nil
	case int16:
		return s, nil
	case int8:
		return int16(s), nil
	case uint:
		return int16(s), nil
	case uint64:
		return int16(s), nil
	case uint32:
		return int16(s), nil
	case uint16:
		return int16(s), nil
	case uint8:
		return int16(s), nil
	case float64:
		return int16(s), nil
	case float32:
		return int16(s), nil
	case string:
		v, err := strconv.ParseInt(s, 0, 0)
		if err == nil {
			return int16(v), nil
		}
		return 0, fmt.Errorf("unable to cast %#v of type %T to int16", i, i)
	case bool:
		if s {
			return 1, nil
		}
		return 0, nil
	case nil:
		return 0, nil
	default:
		return 0, fmt.Errorf("unable to cast %#v of type %T to int16", i, i)
	}
}

// ToInt8 casts an interface to an int8 type, discarding any errors.
func ToInt8(i interface{}) int8 {
	ret, _ := ToInt8E(i)
	return ret
}

// ToInt8E casts an interface to an int8 type.
func ToInt8E(i interface{}) (int8, error) {
	i = indirect(i)

	switch s := i.(type) {
	case int:
		return int8(s), nil
	case int64:
		return int8(s), nil
	case int32:
		return int8(s), nil
	case int16:
		return int8(s), nil
	case int8:
		return s, nil
	case uint:
		return int8(s), nil
	case uint64:
		return int8(s), nil
	case uint32:
		return int8(s), nil
	case uint16:
		return int8(s), nil
	case uint8:
		return int8(s), nil
	case float64:
		return int8(s), nil
	case float32:
		return int8(s), nil
	case string:
		v, err := strconv.ParseInt(s, 0, 0)
		if err == nil {
			return int8(v), nil
		}
		return 0, fmt.Errorf("unable to cast %#v of type %T to int8", i, i)
	case bool:
		if s {
			return 1, nil
		}
		return 0, nil
	case nil:
		return 0, nil
	default:
		return 0, fmt.Errorf("unable to cast %#v of type %T to int8", i, i)
	}
}

// ToInt casts an interface to an int type, discarding any errors.
func ToInt(i interface{}) int {
	ret, _ := ToIntE(i)
	return ret
}

// ToIntE casts an interface to an int type.
func ToIntE(i interface{}) (int, error) {
	i = indirect(i)

	switch s := i.(type) {
	case int:
		return s, nil
	case int64:
		return int(s), nil
	case int32:
		return int(s), nil
	case int16:
		return int(s), nil
	case int8:
		return int(s), nil
	case uint:
		return int(s), nil
	case uint64:
		return int(s), nil
	case uint32:
		return int(s), nil
	case uint16:
		return int(s), nil
	case uint8:
		return int(s), nil
	case float64:
		return int(s), nil
	case float32:
		return int(s), nil
	case string:
		v, err := strconv.ParseInt(s, 0, 0)
		if err == nil {
			return int(v), nil
		}
		return 0, fmt.Errorf("unable to cast %#v of type %T to int", i, i)
	case bool:
		if s {
			return 1, nil
		}
		return 0, nil
	case nil:
		return 0, nil
	default:
		return 0, fmt.Errorf("unable to cast %#v of type %T to int", i, i)
	}
}