ref

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 Go to latest Published: Nov 18, 2020 License: MIT Imports: 12 Imported by: 0

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ref

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ref provides the higher level wraps on golang reflect library.

ref is inspired by oleiade/reflections, which has no more activities for a long time.

Preview Version (WIP)

ref is still a preview version at this time.

Feature

  • reflect helpers: GetField, GetFields, GetTags, ...
  • pretty print: Dump, DumpEx, ...
  • deepclone: Clone, DefaultCloner.Copy(from, to)
  • deepmerge: NewMerger(source).MergeTo(&target)

LICENSE

MIT for free.

Documentation

Overview

Package ref provides the higher level wraps on golang reflect library.

Example (Array) 
Dump([1]interface{}{3}, "x", func(level int, desc string, v reflect.Value) {
	fmt.Println(strings.Repeat("  ", level+1), desc)
})

Output:

Dumping "x" ([1]interface {}):
     x[0].type = int
       x[0].value = 3
Example (Equal) 
//!+
fmt.Println(Equal([]int{1, 2, 3}, []int{1, 2, 3}))        // "true"
fmt.Println(Equal([]string{"foo"}, []string{"bar"}))      // "false"
fmt.Println(Equal([]string(nil), []string{}))             // "true"
fmt.Println(Equal(map[string]int(nil), map[string]int{})) // "true"
//!-

Output:

true
false
true
true
Example (EqualCycle) 
//!+cycle
// Circular linked lists a -> b -> a and c -> c.
type link struct {
	value string
	tail  *link
}
a, b, c := &link{value: "a"}, &link{value: "b"}, &link{value: "c"}
a.tail, b.tail, c.tail = b, a, c
fmt.Println(Equal(a, a)) // "true"
fmt.Println(Equal(b, b)) // "true"
fmt.Println(Equal(c, c)) // "true"
fmt.Println(Equal(a, b)) // "false"
fmt.Println(Equal(a, c)) // "false"
//!-cycle

Output:

true
true
true
false
false
Example (Expr) 
e, _ := eval.Parse("sqrt(A / pi)")
Dump(e, "e", func(level int, desc string, v reflect.Value) {
	fmt.Println(strings.Repeat("  ", level+1), desc)
})

Output:

Dumping "e" (eval.call):
     e.fn = "sqrt"
       e.args[0].type = eval.binary
           e.args[0].value.op = 47
           e.args[0].value.x.type = eval.Var
             e.args[0].value.x.value = "A"
           e.args[0].value.y.type = eval.Var
             e.args[0].value.y.value = "pi"
Example (Interface) 
var i interface{} = 3
Dump(i, "i", func(level int, desc string, v reflect.Value) {
	fmt.Println(strings.Repeat("  ", level+1), desc)
})

Output:

Dumping "i" (int):
   i = 3
Example (Movie) 
//!+movie
type Movie struct {
	Title, Subtitle string
	Year            int
	Color           bool
	Actor           map[string]string
	Oscars          []string
	Sequel          *string
}
//!-movie
//!+strangelove
strangelove := Movie{
	Title:    "Dr. Strangelove",
	Subtitle: "How I Learned to Stop Worrying and Love the Bomb",
	Year:     1964,
	Color:    false,
	Actor: map[string]string{
		"Dr. Strangelove":            "Peter Sellers",
		"Grp. Capt. Lionel Mandrake": "Peter Sellers",
		"Pres. Merkin Muffley":       "Peter Sellers",
		"Gen. Buck Turgidson":        "George C. Scott",
		"Brig. Gen. Jack D. Ripper":  "Sterling Hayden",
		`Maj. T.J. "King" Kong`:      "Slim Pickens",
	},

	Oscars: []string{
		"Best Actor (Nomin.)",
		"Best Adapted Screenplay (Nomin.)",
		"Best Director (Nomin.)",
		"Best Picture (Nomin.)",
	},
}
//!-strangelove
Dump(strangelove, "strangelove", func(level int, desc string, v reflect.Value) {
	fmt.Println(strings.Repeat("  ", level+1), desc)
})

// We don't use an Output: comment since displaying
// a map is nondeterministic.
/*
	//!+output
	Display strangelove (display.Movie):
	strangelove.Title = "Dr. Strangelove"
	strangelove.Subtitle = "How I Learned to Stop Worrying and Love the Bomb"
	strangelove.Year = 1964
	strangelove.Color = false
	strangelove.Actor["Gen. Buck Turgidson"] = "George C. Scott"
	strangelove.Actor["Brig. Gen. Jack D. Ripper"] = "Sterling Hayden"
	strangelove.Actor["Maj. T.J. \"King\" Kong"] = "Slim Pickens"
	strangelove.Actor["Dr. Strangelove"] = "Peter Sellers"
	strangelove.Actor["Grp. Capt. Lionel Mandrake"] = "Peter Sellers"
	strangelove.Actor["Pres. Merkin Muffley"] = "Peter Sellers"
	strangelove.Oscars[0] = "Best Actor (Nomin.)"
	strangelove.Oscars[1] = "Best Adapted Screenplay (Nomin.)"
	strangelove.Oscars[2] = "Best Director (Nomin.)"
	strangelove.Oscars[3] = "Best Picture (Nomin.)"
	strangelove.Sequel = nil
	//!-output
*/il
	//!-output
*/

Output:
Example (NilInterface) 
var w io.Writer
Dump(w, "w", func(level int, desc string, v reflect.Value) {
	fmt.Println(strings.Repeat("  ", level+1), desc)
})

Output:

Dumping "w" (<nil>):
   w = <invalid>
Example (PtrToInterface) 
var w io.Writer
Dump(&w, "&w", func(level int, desc string, v reflect.Value) {
	fmt.Println(strings.Repeat("  ", level+1), desc)
})

Output:

Dumping "&w" (*io.Writer):
     (*&w) = nil
Example (PtrToInterface2) 
var i interface{} = 3
Dump(&i, "&i", func(level int, desc string, v reflect.Value) {
	fmt.Println(strings.Repeat("  ", level+1), desc)
})

Output:

Dumping "&i" (*interface {}):
     (*&i).type = int
       (*&i).value = 3
Example (Slice) 
Dump([]*int{new(int), nil}, "slice", func(level int, desc string, v reflect.Value) {
	fmt.Println(strings.Repeat("  ", level+1), desc)
})

Output:

Dumping "slice" ([]*int):
       (*slice[0]) = 0
     slice[1] = nil
Example (Struct) 
Dump(struct{ x interface{} }{3}, "x", func(level int, desc string, v reflect.Value) {
	fmt.Println(strings.Repeat("  ", level+1), desc)
})

Output:

Dumping "x" (struct { x interface {} }):
     x.x.type = int
       x.x.value = 3

Index

Examples

Constants

View Source 
const (
	// AppName const
	AppName = "ref"
	// Version const
	Version = "0.3.1"
	// VersionInt const
	VersionInt = 0x000301
)

Variables

View Source 
var (
	DefaultNameMappingRule NameMappingRule = func(fromName string) (toName string, mapped bool) {
		return
	}

	DefaultCloner = buildDefaultCloner()

	LazyGobCopier = lazyCopier{}
)

Functions

func Any 

func Any(value interface{}) string

Any formats any value as a string.

func CanIsNil 

func CanIsNil(v reflect.Value) bool

func CanIsZero 

func CanIsZero(v reflect.Value) bool

func Captalize 

func Captalize(s string) string

Captalize returns a copy of the string s with all Unicode letters that begin words mapped to their Unicode title case.

BUG(rsc): The rule Title uses for word boundaries does not handle Unicode punctuation properly.

func Clone 

func Clone(fromVar, toVar interface{}, opts ...CloneOpt) interface{}

Clone makes a deep clone of 'from'.

Note that toVar should be a pointer to a struct while you're cloning on a struct, for example: 

var u1 = User{Name:"aa"}
var u2 = new(User)
fmt.Println(ref.Clone(u1, u2))

Clone will make the cloned object from fromVar with Cloneable interface. It's talking about the better way to clone an object is implement the Cloneable interface.

For the normally object cloning, Clone uses Golang reflect feature. So we can only clone the exported fields of a struct in this case. The unexported fields will be ignored by default ( see also cloner.IgnoreUnexportedError ) .

func Dump 

func Dump(obj interface{}, objDesc string, dumper func(level int, desc string, v reflect.Value))

Dump prints the structure and value of an object with pretty format

func DumpEx 

func DumpEx(obj interface{}, objDesc string, dumper func(level int, desc string, v reflect.Value), preDumper, postDumper func(v reflect.Value))

DumpEx prints the structure and value of an object with pretty format

func Equal 

func Equal(x, y interface{}) bool

!+comparison Equal reports whether x and y are deeply equal. !-comparison

Map keys are always compared with ==, not deeply. (This matters for keys containing pointers or interfaces.) !+comparison

func Fields 

func Fields(obj interface{}) ([]string, error)

Fields returns the struct fields names list. obj can whether be a structure or pointer to structure.

Example 
package main

import (
	"fmt"
	"github.com/hedzr/ref"
)

type MyStruct struct {
	MyEmbeddedStruct
	FirstField  string `matched:"first tag"`
	SecondField int    `matched:"second tag"`
	ThirdField  string `unmatched:"third tag"`
}

type MyEmbeddedStruct struct {
	EmbeddedField string
}

func main() {
	s := MyStruct{
		FirstField:  "first value",
		SecondField: 2,
		ThirdField:  "third value",
	}

	var fields []string

	// Fields will list every structure exportable fields.
	// Here, it's content would be equal to:
	// []string{"FirstField", "SecondField", "ThirdField"}
	fields, _ = ref.Fields(s)
	fmt.Println(fields)
}

Output:

func FieldsDeep 

func FieldsDeep(obj interface{}) ([]string, error)

FieldsDeep returns "flattened" fields (fields from anonymous inner structs are treated as normal fields)

func FieldsDeeper 

func FieldsDeeper(obj interface{}, fn func(owner *reflect.Value, thisField reflect.StructField, this reflect.Value)) error

FieldsDeeper returns "flattened" fields (fields from anonymous inner structs are treated as normal fields)

func FieldsTagDeeper 

func FieldsTagDeeper(obj interface{}, tagKey string, fn func(owner *reflect.Value, thisField reflect.StructField, this reflect.Value, tagValue string)) error

FieldsTagDeeper returns "flattened" fields (fields from anonymous inner structs are treated as normal fields)

func GetField 

func GetField(obj interface{}, fieldName string) (field interface{}, err error)

GetField returns the value of the provided obj field. obj can whether be a structure or pointer to structure.

Example 
package main

import (
	"fmt"
	"github.com/hedzr/ref"
	"log"
)

type MyStruct struct {
	MyEmbeddedStruct
	FirstField  string `matched:"first tag"`
	SecondField int    `matched:"second tag"`
	ThirdField  string `unmatched:"third tag"`
}

type MyEmbeddedStruct struct {
	EmbeddedField string
}

func main() {
	s := MyStruct{
		FirstField:  "first value",
		SecondField: 2,
		ThirdField:  "third value",
	}

	fieldsToExtract := []string{"FirstField", "ThirdField"}

	for _, fieldName := range fieldsToExtract {
		value, err := ref.GetField(s, fieldName)
		if err != nil {
			log.Fatal(err)
		}
		fmt.Println(value)
	}
}

Output:

func GetFieldKind 

func GetFieldKind(obj interface{}, fieldName string) (kind reflect.Kind, err error)

GetFieldKind returns the kind of the provided obj field. obj can whether be a structure or pointer to structure.

Example 
package main

import (
	"fmt"
	"github.com/hedzr/ref"
	"log"
	"reflect"
)

type MyStruct struct {
	MyEmbeddedStruct
	FirstField  string `matched:"first tag"`
	SecondField int    `matched:"second tag"`
	ThirdField  string `unmatched:"third tag"`
}

type MyEmbeddedStruct struct {
	EmbeddedField string
}

func main() {
	s := MyStruct{
		FirstField:  "first value",
		SecondField: 2,
		ThirdField:  "third value",
	}

	var firstFieldKind reflect.Kind
	var secondFieldKind reflect.Kind
	var err error

	// GetFieldKind will return reflect.String
	firstFieldKind, err = ref.GetFieldKind(s, "FirstField")
	if err != nil {
		log.Fatal(err)
	}
	fmt.Println(firstFieldKind)

	// GetFieldKind will return reflect.Int
	secondFieldKind, err = ref.GetFieldKind(s, "SecondField")
	if err != nil {
		log.Fatal(err)
	}
	fmt.Println(secondFieldKind)
}

Output:

func GetFieldKinds 

func GetFieldKinds(obj interface{}, fieldNames ...string) (kinds []reflect.Kind, err error)

GetFieldKind returns the kind of the provided obj field. obj can whether be a structure or pointer to structure.

func GetFieldTag 

func GetFieldTag(obj interface{}, tagKey string, fieldName string) (tagValue string, err error)

GetFieldTag returns the provided obj field tag value. obj can whether be a structure or pointer to structure.

Example 
package main

import (
	"fmt"
	"github.com/hedzr/ref"
	"log"
)

type MyStruct struct {
	MyEmbeddedStruct
	FirstField  string `matched:"first tag"`
	SecondField int    `matched:"second tag"`
	ThirdField  string `unmatched:"third tag"`
}

type MyEmbeddedStruct struct {
	EmbeddedField string
}

func main() {
	s := MyStruct{}

	tag, err := ref.GetFieldTag(s, "matched", "FirstField")
	if err != nil {
		log.Fatal(err)
	}
	fmt.Println(tag)

	tag, err = ref.GetFieldTag(s, "unmatched", "ThirdField")
	if err != nil {
		log.Fatal(err)
	}
	fmt.Println(tag)
}

Output:

func GetFieldTags 

func GetFieldTags(obj interface{}, tagKey string, fieldNames ...string) (tagValues []string, err error)

GetFieldTag returns the provided obj field tag value. obj can whether be a structure or pointer to structure.

func GetFieldType 

func GetFieldType(obj interface{}, fieldName string) (typ string, err error)

GetFieldType returns the kind of the provided obj field. obj can whether be a structure or pointer to structure.

Example 
package main

import (
	"fmt"
	"github.com/hedzr/ref"
	"log"
)

type MyStruct struct {
	MyEmbeddedStruct
	FirstField  string `matched:"first tag"`
	SecondField int    `matched:"second tag"`
	ThirdField  string `unmatched:"third tag"`
}

type MyEmbeddedStruct struct {
	EmbeddedField string
}

func main() {
	s := MyStruct{
		FirstField:  "first value",
		SecondField: 2,
		ThirdField:  "third value",
	}

	var firstFieldType string
	var secondFieldType string
	var err error

	// GetFieldType will return reflect.String
	firstFieldType, err = ref.GetFieldType(s, "FirstField")
	if err != nil {
		log.Fatal(err)
	}
	fmt.Println(firstFieldType)

	// GetFieldType will return reflect.Int
	secondFieldType, err = ref.GetFieldType(s, "SecondField")
	if err != nil {
		log.Fatal(err)
	}
	fmt.Println(secondFieldType)
}

Output:

func GetFieldTypes 

func GetFieldTypes(obj interface{}, fieldNames ...string) (types []string, err error)

GetFieldType returns the kind of the provided obj field. obj can whether be a structure or pointer to structure.

func GetFields 

func GetFields(obj interface{}, fieldNames ...string) (fields []interface{}, err error)

GetFields returns the value of the provided obj field. obj can whether be a structure or pointer to structure.

func GetUnexportedField 

func GetUnexportedField(field reflect.Value) interface{}

func HasAnyField 

func HasAnyField(obj interface{}, names ...string) (has bool)

HasAnyField checks the existences of the given name list

func HasField 

func HasField(obj interface{}, name string) (has bool)

HasField checks if the provided field name is part of a struct. obj can whether be a structure or pointer to structure.

Example 
package main

import (
	"fmt"
	"github.com/hedzr/ref"
)

type MyStruct struct {
	MyEmbeddedStruct
	FirstField  string `matched:"first tag"`
	SecondField int    `matched:"second tag"`
	ThirdField  string `unmatched:"third tag"`
}

type MyEmbeddedStruct struct {
	EmbeddedField string
}

func main() {
	s := MyStruct{
		FirstField:  "first value",
		SecondField: 2,
		ThirdField:  "third value",
	}

	// has == true
	has := ref.HasField(s, "FirstField")
	fmt.Println(has)

	// has == false
	has = ref.HasField(s, "FourthField")
	fmt.Println(has)
}

Output:

func IndirectType 

func IndirectType(reflectType reflect.Type) reflect.Type

func IndirectTypeRecursive 

func IndirectTypeRecursive(reflectType reflect.Type) reflect.Type

func IndirectValue 

func IndirectValue(reflectValue reflect.Value) reflect.Value

func IndirectValueRecursive 

func IndirectValueRecursive(reflectValue reflect.Value) reflect.Value

func IsNil 

func IsNil(v reflect.Value) bool

IsNil reports whether its argument v is nil. The argument must be a chan, func, interface, map, pointer, or slice value; if it is not, IsNil panics. Note that IsNil is not always equivalent to a regular comparison with nil in Go. For example, if v was created by calling ValueOf with an uninitialized interface variable i, i==nil will be true but v.IsNil will panic as v will be the zero Value.

func IsNilSafe 

func IsNilSafe(v reflect.Value) bool

IsNilSafe reports whether its argument v is nil. The argument must be a chan, func, interface, map, pointer, or slice value; if it is not, IsNil panics. Note that IsNil is not always equivalent to a regular comparison with nil in Go. For example, if v was created by calling ValueOf with an uninitialized interface variable i, i==nil will be true but v.IsNil will panic as v will be the zero Value.

func IsZero 

func IsZero(v reflect.Value) bool

IsZero reports whether v is the zero value for its type. It panics if the argument is invalid.

func IsZeroSafe 

func IsZeroSafe(v reflect.Value) bool

IsZeroSafe reports whether v is the zero value for its type. It panics if the argument is invalid.

func Items 

func Items(obj interface{}) (map[string]interface{}, error)

Items returns the field - value struct pairs as a map. obj can whether be a structure or pointer to structure.

Example 
package main

import (
	"fmt"
	"github.com/hedzr/ref"
)

type MyStruct struct {
	MyEmbeddedStruct
	FirstField  string `matched:"first tag"`
	SecondField int    `matched:"second tag"`
	ThirdField  string `unmatched:"third tag"`
}

type MyEmbeddedStruct struct {
	EmbeddedField string
}

func main() {
	s := MyStruct{
		FirstField:  "first value",
		SecondField: 2,
		ThirdField:  "third value",
	}

	var structItems map[string]interface{}

	// Items will return a field name to
	// field value map
	structItems, _ = ref.Items(s)
	fmt.Println(structItems)
}

Output:

func ItemsDeep 

func ItemsDeep(obj interface{}) (map[string]interface{}, error)

FieldsDeep returns "flattened" items (fields from anonymous inner structs are treated as normal fields)

Example 
package main

import (
	"fmt"
	"github.com/hedzr/ref"
)

type MyStruct struct {
	MyEmbeddedStruct
	FirstField  string `matched:"first tag"`
	SecondField int    `matched:"second tag"`
	ThirdField  string `unmatched:"third tag"`
}

type MyEmbeddedStruct struct {
	EmbeddedField string
}

func main() {
	s := MyStruct{
		FirstField:  "first value",
		SecondField: 2,
		ThirdField:  "third value",
		MyEmbeddedStruct: MyEmbeddedStruct{
			EmbeddedField: "embedded value",
		},
	}

	var structItems map[string]interface{}

	// ItemsDeep will return a field name to
	// field value map, including fields from
	// anonymous embedded structs
	structItems, _ = ref.ItemsDeep(s)
	fmt.Println(structItems)
}

Output:

func SetField 

func SetField(obj interface{}, name string, value interface{}) (err error)

SetField sets the provided obj field with provided value. obj param has to be a pointer to a struct, otherwise it will soundly fail. Provided value type should match with the struct field you're trying to set.

Example 
package main

import (
	"github.com/hedzr/ref"
	"log"
)

type MyStruct struct {
	MyEmbeddedStruct
	FirstField  string `matched:"first tag"`
	SecondField int    `matched:"second tag"`
	ThirdField  string `unmatched:"third tag"`
}

type MyEmbeddedStruct struct {
	EmbeddedField string
}

func main() {
	s := MyStruct{
		FirstField:  "first value",
		SecondField: 2,
		ThirdField:  "third value",
	}

	// In order to be able to set the structure's values,
	// a pointer to it has to be passed to it.
	err := ref.SetField(&s, "FirstField", "new value")
	if err != nil {
		log.Fatal(err)
	}

	// If you try to set a field's value using the wrong type,
	// an error will be returned
	err = ref.SetField(&s, "FirstField", 123) // err != nil
	if err != nil {
		log.Fatal(err)
	}
}

Output:

func SetNil 

func SetNil(to reflect.Value)

func SetUnexportedField 

func SetUnexportedField(field reflect.Value, value interface{})

func SetZero 

func SetZero(to reflect.Value)

func Tags 

func Tags(obj interface{}, key string) (map[string]string, error)

Tags lists the struct tag fields. obj can whether be a structure or pointer to structure.

Example 
package main

import (
	"fmt"
	"github.com/hedzr/ref"
)

type MyStruct struct {
	MyEmbeddedStruct
	FirstField  string `matched:"first tag"`
	SecondField int    `matched:"second tag"`
	ThirdField  string `unmatched:"third tag"`
}

type MyEmbeddedStruct struct {
	EmbeddedField string
}

func main() {
	s := MyStruct{
		FirstField:  "first value",
		SecondField: 2,
		ThirdField:  "third value",
	}

	var structTags map[string]string

	// Tags will return a field name to tag content
	// map. Nota that only field with the tag name
	// you've provided which will be matched.
	// Here structTags will contain:
	// {
	//     "FirstField": "first tag",
	//     "SecondField": "second tag",
	// }
	structTags, _ = ref.Tags(s, "matched")
	fmt.Println(structTags)
}

Output:

func TagsDeep 

func TagsDeep(obj interface{}, key string) (map[string]string, error)

FieldsDeep returns "flattened" tags (fields from anonymous inner structs are treated as normal fields)

func TryConvert 

func TryConvert(v reflect.Value, t reflect.Type) (out reflect.Value, err error)

TryConvert calls reflect.Convert safely, without panic threw.

Types

type CloneOpt 

type CloneOpt func(c *cloner)

CloneOpt is functional option functor for Clone()

func WithEachFieldAlways 

func WithEachFieldAlways(b bool) CloneOpt

func WithIgnoreUnexportedError 

func WithIgnoreUnexportedError(ignored bool) CloneOpt

func WithIgnoredFieldNames 

func WithIgnoredFieldNames(names ...string) CloneOpt

WithIgnoredFieldNames appends the ignored name list to the Cloner operator.

func WithKeepIfFromIsNilOrZero 

func WithKeepIfFromIsNilOrZero(keepIfFromIsNil, keepIfFromIsZero bool) CloneOpt

func WithNameMappings 

func WithNameMappings(m map[string]string) CloneOpt

func WithNameMappingsRule 

func WithNameMappingsRule(rule NameMappingRule) CloneOpt

func WithZeroIfEqualsFrom 

func WithZeroIfEqualsFrom(b bool) CloneOpt

type Cloneable 

type Cloneable interface {
	// Clone will always return a new cloned object instance on 'this' object
	Clone() interface{}
}

Cloneable interface represents a cloneable object

type Cloner 

type Cloner interface {
	Copy(fromVar, toVar interface{}, Opts ...Opt) (err error)
}

Cloner provides a copier interface for the deep clone algor.

type Field 

type Field struct {
	Type  reflect.StructField
	Value reflect.Value
}

func (Field) GetUnexportedField 

func (field Field) GetUnexportedField() interface{}

func (Field) SetUnexportedField 

func (field Field) SetUnexportedField(value interface{})

type Merger 

type Merger struct {
	IgnoreUnexportedError bool
	// contains filtered or unexported fields
}

func NewMerger 

func NewMerger(inputMap interface{}) *Merger

NewMerger return a merging operator for your input map instance. 

m := map[string]interface( "a": 1 }
var targetMap map[string]interface{}
NewMerger(m).MergeTo(&targetMap)

func (*Merger) HasError 

func (m *Merger) HasError() bool

func (*Merger) MergeTo 

func (m *Merger) MergeTo(to interface{}) (err error)

func (*Merger) Reset 

func (m *Merger) Reset()

type NameMappingRule 

type NameMappingRule func(fromName string) (toName string, mapped bool)

type Opt 

type Opt func(c Cloner)

Opt is functional option functor for Cloner

type Type 

type Type struct {
	reflect.Type
}

Type is a struct wrapped on reflect.Type

func TypeOf 

func TypeOf(obj interface{}) Type

TypeOf returns the reflection Type that represents the dynamic type of i. If i is a nil interface value, TypeOf returns nil.

func (Type) IndirectType 

func (t Type) IndirectType() Type

func (Type) IndirectTypeRecursive 

func (t Type) IndirectTypeRecursive() Type

type Value 

type Value struct {
	reflect.Value
}

Value is a struct wrapped on reflect.Value

func ValueOf 

func ValueOf(obj interface{}) Value

ValueOf is a copy of reflect.ValueOf(i) but wrapped as ref.Value

both the original object and its reflect.Value obj can be passed into ValueOf. 

import "github.com/hedzr/assert"
import "github.com/hedzr/ref"
import "reflect"
a := &User{Name:"me"}
va := reflect.ValueOf(a)
vv1 := ref.ValueOf(a)
vv2 := ref.ValueOf(va)
assert.Equal(t, vv1, vv2) // vv1 and vv2 should be always equivalent.

func (Value) GetValue 

func (v Value) GetValue() (val interface{})

func (Value) IndirectType 

func (v Value) IndirectType() Type

func (Value) IndirectTypeRecursive 

func (v Value) IndirectTypeRecursive() Type

func (Value) IndirectValue 

func (v Value) IndirectValue() Value

func (Value) IndirectValueRecursive 

func (v Value) IndirectValueRecursive() Value

func (Value) IsComplex 

func (v Value) IsComplex() bool

func (Value) IsFloat 

func (v Value) IsFloat() bool

func (Value) IsInt 

func (v Value) IsInt() bool

func (Value) IsKindComplex 

func (v Value) IsKindComplex(k reflect.Kind) bool

func (Value) IsKindFloat 

func (v Value) IsKindFloat(k reflect.Kind) bool

func (Value) IsKindInt 

func (v Value) IsKindInt(k reflect.Kind) bool

func (Value) IsKindInteger 

func (v Value) IsKindInteger(k reflect.Kind) bool

func (Value) IsKindPointer 

func (v Value) IsKindPointer(k reflect.Kind) bool

func (Value) IsKindStruct 

func (v Value) IsKindStruct(k reflect.Kind) bool

func (Value) IsKindUint 

func (v Value) IsKindUint(k reflect.Kind) bool

func (Value) IsNil 

func (v Value) IsNil() bool

func (Value) IsPointer 

func (v Value) IsPointer() bool

func (Value) IsString 

func (v Value) IsString() bool

func (Value) IsStruct 

func (v Value) IsStruct() bool

func (Value) IsZero 

func (v Value) IsZero() bool

IsZero reports whether v is the zero value for its type. It panics if the argument is invalid.

func (Value) PtrToIndirectValueRecursive 

func (v Value) PtrToIndirectValueRecursive() Value

func (Value) SetNil 

func (v Value) SetNil()

func (Value) SetZero 

func (v Value) SetZero()

func (Value) TryConvert 

func (v Value) TryConvert(t reflect.Type) (out reflect.Value, err error)

TryConvert calls reflect.Convert safely, without panic threw.

Notes

Bugs

  • The rule Title uses for word boundaries does not handle Unicode punctuation properly.

  • The rule Title uses for word boundaries does not handle Unicode punctuation properly.

Source Files

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Directories

Path Synopsis
Package eval is a copy from https://github.com/adonovan/gopl.io
 Package eval is a copy from https://github.com/adonovan/gopl.io

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