README
¶
goclub/type
go get github.com/goclub/type
go 的类型系统没有 int? 这样的语法来表达一些基础字段是 nil 还是zero value.有些业务场景需要实现类似 int? 来解决问题.
goclub/type 提供了 Option 类型来解决这类问题.
package main
import (
xtype "github.com/goclub/type"
"log"
)
// 利用 xtype.OptionInt 判断是否设置 age
func SetData(name string, age xtype.OptionInt) {
if age.Valid() {
log.Print("set age", age.Unwrap())
} else {
log.Print("not set age")
}
}
func main() {
SetData("goclub", xtype.Int(18)) // set age 18
SetData("goclub", xtype.OptionInt{}) // not set age
}
xtype.OptionInt源码:
package xtype
type OptionInt struct {
int int
valid bool
}
func (o OptionInt) Valid() bool {
return o.valid
}
func (o OptionInt) Unwrap() int {
if o.valid {
return o.int
}
return 0
}
func Int(i int) OptionInt {
return OptionInt{ i, true}
}
其他基础类型也都实现了 Option 方法,通过 xtype.类型() 获取有效值, xtype.Option类型{} 表示无效值.
Documentation
¶
Index ¶
- type OptionBool
- type OptionBytes
- type OptionComplex128
- type OptionComplex64
- type OptionDuration
- type OptionFloat32
- type OptionFloat64
- type OptionInt
- type OptionInt16
- type OptionInt32
- type OptionInt64
- type OptionInt8
- type OptionRunes
- type OptionString
- type OptionStrings
- type OptionTime
- type OptionUint
- type OptionUint16
- type OptionUint32
- type OptionUint64
- type OptionUint8
Examples ¶
Constants ¶
This section is empty.
Variables ¶
This section is empty.
Functions ¶
This section is empty.
Types ¶
type OptionBool ¶
type OptionBool struct {
// contains filtered or unexported fields
}
func Bool ¶
func Bool(b bool) OptionBool
func (OptionBool) Unwrap ¶
func (o OptionBool) Unwrap() bool
func (OptionBool) Valid ¶
func (o OptionBool) Valid() bool
type OptionBytes ¶
type OptionBytes struct {
// contains filtered or unexported fields
}
func Bytes ¶
func Bytes(bytes []byte) OptionBytes
func (OptionBytes) Unwrap ¶
func (o OptionBytes) Unwrap() []byte
func (OptionBytes) Valid ¶
func (o OptionBytes) Valid() bool
type OptionComplex128 ¶
type OptionComplex128 struct {
// contains filtered or unexported fields
}
func Complex128 ¶
func Complex128(c complex128) OptionComplex128
func (OptionComplex128) Unwrap ¶
func (o OptionComplex128) Unwrap() complex128
func (OptionComplex128) Valid ¶
func (o OptionComplex128) Valid() bool
type OptionComplex64 ¶
type OptionComplex64 struct {
// contains filtered or unexported fields
}
func Complex64 ¶
func Complex64(c complex64) OptionComplex64
func (OptionComplex64) Unwrap ¶
func (o OptionComplex64) Unwrap() complex64
func (OptionComplex64) Valid ¶
func (o OptionComplex64) Valid() bool
type OptionDuration ¶
type OptionDuration struct {
// contains filtered or unexported fields
}
func Duration ¶
func Duration(d time.Duration) OptionDuration
func (OptionDuration) Unwrap ¶
func (o OptionDuration) Unwrap() time.Duration
func (OptionDuration) Valid ¶
func (o OptionDuration) Valid() bool
type OptionFloat32 ¶
type OptionFloat32 struct {
// contains filtered or unexported fields
}
func Float32 ¶
func Float32(f float32) OptionFloat32
func (OptionFloat32) Unwrap ¶
func (o OptionFloat32) Unwrap() float32
func (OptionFloat32) Valid ¶
func (o OptionFloat32) Valid() bool
type OptionFloat64 ¶
type OptionFloat64 struct {
// contains filtered or unexported fields
}
func Float64 ¶
func Float64(f float64) OptionFloat64
func (OptionFloat64) Unwrap ¶
func (o OptionFloat64) Unwrap() float64
func (OptionFloat64) Valid ¶
func (o OptionFloat64) Valid() bool
type OptionInt ¶
type OptionInt struct {
// contains filtered or unexported fields
}
func Int ¶
Example ¶
package main
import (
xtype "github.com/goclub/type"
"log"
)
// 必须设置 age
func SetDataV1(name string, age int) {
log.Print("set age", age)
}
// 可通过 notSetAge 控制不设置 age
func SetDataV2(name string, age int, notSetAge bool) {
if notSetAge {
log.Print("not set age")
} else {
log.Print("set age", age)
}
}
// 传递nil则表示不设置 age
func SetDataV3(name string, age *int) {
if age == nil {
log.Print("not set age")
} else {
log.Print("set age", *age)
}
}
// 利用 xtype.OptionInt 判断是否设置 age
func SetDataV4(name string, age xtype.OptionInt) {
if age.Valid() {
log.Print("set age", age.Unwrap())
} else {
log.Print("not set age")
}
}
func main() {
SetDataV1("goclub", 0) // set age 0
SetDataV1("goclub", 18) // set age 18
SetDataV2("goclub", 18, false) // set age 18
SetDataV2("goclub", 0, true) // not set age
agev3 := 18
SetDataV3("goclub", &agev3) // set age 18
SetDataV3("goclub", nil) // not set age
SetDataV4("goclub", xtype.Int(18)) // set age 18
SetDataV4("goclub", xtype.OptionInt{}) // not set age
}
Output:
type OptionInt16 ¶
type OptionInt16 struct {
// contains filtered or unexported fields
}
func Int16 ¶
func Int16(i int16) OptionInt16
func (OptionInt16) Unwrap ¶
func (o OptionInt16) Unwrap() int16
func (OptionInt16) Valid ¶
func (o OptionInt16) Valid() bool
type OptionInt32 ¶
type OptionInt32 struct {
// contains filtered or unexported fields
}
func Int32 ¶
func Int32(i int32) OptionInt32
func (OptionInt32) Unwrap ¶
func (o OptionInt32) Unwrap() int32
func (OptionInt32) Valid ¶
func (o OptionInt32) Valid() bool
type OptionInt64 ¶
type OptionInt64 struct {
// contains filtered or unexported fields
}
func Int64 ¶
func Int64(i int64) OptionInt64
func (OptionInt64) Unwrap ¶
func (o OptionInt64) Unwrap() int64
func (OptionInt64) Valid ¶
func (o OptionInt64) Valid() bool
type OptionInt8 ¶
type OptionInt8 struct {
// contains filtered or unexported fields
}
func Int8 ¶
func Int8(i int8) OptionInt8
func (OptionInt8) Unwrap ¶
func (o OptionInt8) Unwrap() int8
func (OptionInt8) Valid ¶
func (o OptionInt8) Valid() bool
type OptionRunes ¶
type OptionRunes struct {
// contains filtered or unexported fields
}
func Runes ¶
func Runes(runes []rune) OptionRunes
func (OptionRunes) Unwrap ¶
func (o OptionRunes) Unwrap() []rune
func (OptionRunes) Valid ¶
func (o OptionRunes) Valid() bool
type OptionString ¶
type OptionString struct {
// contains filtered or unexported fields
}
func String ¶
func String(s string) OptionString
func (OptionString) Unwrap ¶
func (o OptionString) Unwrap() string
func (OptionString) Valid ¶
func (o OptionString) Valid() bool
type OptionStrings ¶
type OptionStrings struct {
// contains filtered or unexported fields
}
func Strings ¶
func Strings(strings []string) OptionStrings
func (OptionStrings) Unwrap ¶
func (o OptionStrings) Unwrap() []string
func (OptionStrings) Valid ¶
func (o OptionStrings) Valid() bool
type OptionTime ¶
type OptionTime struct {
// contains filtered or unexported fields
}
func Time ¶
func Time(t time.Time) OptionTime
func (OptionTime) Unwrap ¶
func (o OptionTime) Unwrap() time.Time
func (OptionTime) Valid ¶
func (o OptionTime) Valid() bool
type OptionUint ¶
type OptionUint struct {
// contains filtered or unexported fields
}
func Uint ¶
func Uint(i uint) OptionUint
func (OptionUint) Unwrap ¶
func (o OptionUint) Unwrap() uint
func (OptionUint) Valid ¶
func (o OptionUint) Valid() bool
type OptionUint16 ¶
type OptionUint16 struct {
// contains filtered or unexported fields
}
func Uint16 ¶
func Uint16(i uint16) OptionUint16
func (OptionUint16) Unwrap ¶
func (o OptionUint16) Unwrap() uint16
func (OptionUint16) Valid ¶
func (o OptionUint16) Valid() bool
type OptionUint32 ¶
type OptionUint32 struct {
// contains filtered or unexported fields
}
func Uint32 ¶
func Uint32(i uint32) OptionUint32
func (OptionUint32) Unwrap ¶
func (o OptionUint32) Unwrap() uint32
func (OptionUint32) Valid ¶
func (o OptionUint32) Valid() bool
type OptionUint64 ¶
type OptionUint64 struct {
// contains filtered or unexported fields
}
func Uint64 ¶
func Uint64(i uint64) OptionUint64
func (OptionUint64) Unwrap ¶
func (o OptionUint64) Unwrap() uint64
func (OptionUint64) Valid ¶
func (o OptionUint64) Valid() bool
type OptionUint8 ¶
type OptionUint8 struct {
// contains filtered or unexported fields
}
func Uint8 ¶
func Uint8(i uint8) OptionUint8
func (OptionUint8) Unwrap ¶
func (o OptionUint8) Unwrap() uint8
func (OptionUint8) Valid ¶
func (o OptionUint8) Valid() bool
Source Files
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