improve indirect

README.md

@@ -19,7 +19,7 @@ go get -u github.com/shockerli/cvt
 
 ## Usage
 
-[中文说明](README_ZH.md)
+English | [中文](README_ZH.md)
 
 ### with `error`
 
@@ -113,9 +113,8 @@ cvt.Float("hello", 12.34)   // 12.34
 ### slice
 - `ColumnsE`: the values from a single column in the input array/slice/map of struct/map, `[]interface{}`
 - `FieldE`: the field value from map/struct, `interface{}`
-- `KeysE`: the keys of map, `[]interface{}`
-- `Slice`
-- `SliceE`: convert an interface to a `[]interface{}` type
+- `KeysE`: the keys of map, or fields of struct, `[]interface{}`
+- `Slice` / `SliceE`: convert an interface to a `[]interface{}` type
 - `SliceIntE`: convert an interface to a `[]int` type
 - `SliceInt64E`: convert an interface to a `[]int64` type
 - `SliceFloat64E`: convert an interface to a `[]float64` type

README_ZH.md

@@ -7,7 +7,7 @@
 [![codecov](https://codecov.io/gh/shockerli/cvt/branch/master/graph/badge.svg)](https://codecov.io/gh/shockerli/cvt)
 ![GitHub](https://img.shields.io/github/license/shockerli/cvt)
 
-> 简单、安全的转换任意类型值，包括自定义类型
+> 一个简单、安全、高效的转换任意数据类型的 Go 语言工具包，支持自定义类型、提取结构体字段和值
 
 ## 安装
 
@@ -17,7 +17,7 @@ go get -u github.com/shockerli/cvt
 
 ## 使用
 
-[English](README.md)
+中文 | [English](README.md)
 
 ### 支持 `error`
 
@@ -111,9 +111,8 @@ cvt.Float("hello", 12.34)       // 12.34
 ### slice
 - `ColumnsE`: 类似于 PHP 中的 `array_column`，`FieldE` 函数的切片版本，返回 `[]interface{}`
 - `FieldE`: 取 `map` 或 `struct` 的字段值，返回 `interface{}`
-- `KeysE`: 取 `map` 的键名，返回 `[]interface{}`
-- `Slice`
-- `SliceE`: 转换成 `[]interface{}`
+- `KeysE`: 取 `map` 的键名，或结构体的字段名，返回 `[]interface{}`
+- `Slice` / `SliceE`: 转换成 `[]interface{}`
 - `SliceIntE`: 转换成 `[]int`
 - `SliceInt64E`: 转换成 `[]int64`
 - `SliceFloat64E`: 转换成 `[]float64`

bool.go

@@ -21,7 +21,7 @@ func Bool(v interface{}, def ...bool) bool {
 
 // BoolE convert an interface to a bool type
 func BoolE(val interface{}) (bool, error) {
-	v, rk, rv := indirect(val)
+	v, rv := indirect(val)
 
 	switch vv := v.(type) {
 	case bool:
@@ -40,7 +40,7 @@ func BoolE(val interface{}) (bool, error) {
 		return false, nil
 	}
 
-	switch rk.Kind() {
+	switch rv.Kind() {
 	// by elem length
 	case reflect.Array, reflect.Slice, reflect.Map:
 		return rv.Len() > 0, nil

cvte.go

@@ -22,9 +22,9 @@ func FieldE(val interface{}, field interface{}) (interface{}, error) {
 	}
 
 	sf := String(field) // match with the String of field, so field can be any type
-	_, rt, rv := indirect(val)
+	_, rv := indirect(val)
 
-	switch rt.Kind() {
+	switch rv.Kind() {
 	case reflect.Map: // key of map
 		for _, key := range rv.MapKeys() {
 			if String(key.Interface()) == sf {
@@ -42,10 +42,10 @@ func FieldE(val interface{}, field interface{}) (interface{}, error) {
 }
 
 // return the values of struct fields, and deep find the embedded fields
-func deepStructValues(rt reflect.Type, rv reflect.Value) (sl []interface{}) {
+func deepStructValues(rv reflect.Value) (sl []interface{}) {
 	for j := 0; j < rv.NumField(); j++ {
-		if rt.Field(j).Anonymous {
-			sl = append(sl, deepStructValues(rt.Field(j).Type, rv.Field(j))...)
+		if rv.Type().Field(j).Anonymous {
+			sl = append(sl, deepStructValues(rv.Field(j))...)
 		} else if rv.Field(j).CanInterface() {
 			sl = append(sl, rv.Field(j).Interface())
 		}
@@ -63,16 +63,15 @@ func sortedMapKeys(v reflect.Value) (s []reflect.Value) {
 }
 
 // returns the value with base type
-func indirect(a interface{}) (val interface{}, rt reflect.Type, rv reflect.Value) {
+func indirect(a interface{}) (val interface{}, rv reflect.Value) {
 	if a == nil {
 		return
 	}
 
-	rt = reflect.TypeOf(a)
 	rv = reflect.ValueOf(a)
 	val = rv.Interface()
 
-	switch rt.Kind() {
+	switch rv.Kind() {
 	case reflect.Ptr: // indirect the base type, if is been referenced many times
 		for rv.Kind() == reflect.Ptr {
 			// stop indirect until nil, avoid stack overflow

float.go

@@ -21,7 +21,7 @@ func Float64(v interface{}, def ...float64) float64 {
 
 // Float64E convert an interface to a float64 type
 func Float64E(val interface{}) (float64, error) {
-	v, _, rv := indirect(val)
+	v, rv := indirect(val)
 
 	switch vv := v.(type) {
 	case nil:

int.go

@@ -330,7 +330,7 @@ func convUint64(val interface{}) (uint64, error) {
 	}
 
 	// indirect type
-	v, _, rv := indirect(val)
+	v, rv := indirect(val)
 	switch vv := v.(type) {
 	case nil:
 		return 0, nil
@@ -423,7 +423,7 @@ func convInt64(val interface{}) (int64, error) {
 	}
 
 	// indirect type
-	v, _, rv := indirect(val)
+	v, rv := indirect(val)
 	switch vv := v.(type) {
 	case nil:
 		return 0, nil

slice.go

@@ -24,9 +24,9 @@ func SliceE(val interface{}) (sl []interface{}, err error) {
 		return nil, errUnsupportedTypeNil
 	}
 
-	_, rt, rv := indirect(val)
+	_, rv := indirect(val)
 
-	switch rt.Kind() {
+	switch rv.Kind() {
 	case reflect.String:
 		for _, vvv := range rv.String() {
 			sl = append(sl, vvv)
@@ -43,7 +43,7 @@ func SliceE(val interface{}) (sl []interface{}, err error) {
 		}
 		return
 	case reflect.Struct:
-		sl = deepStructValues(rt, rv)
+		sl = deepStructValues(rv)
 		return
 	}
 
@@ -128,9 +128,9 @@ func ColumnsE(val interface{}, field interface{}) (sl []interface{}, err error)
 		return nil, errUnsupportedTypeNil
 	}
 
-	_, rt, rv := indirect(val)
+	_, rv := indirect(val)
 
-	switch rt.Kind() {
+	switch rv.Kind() {
 	case reflect.Slice, reflect.Array:
 		for j := 0; j < rv.Len(); j++ {
 			vv, e := FieldE(rv.Index(j).Interface(), field)
@@ -152,7 +152,7 @@ func ColumnsE(val interface{}, field interface{}) (sl []interface{}, err error)
 		return
 	}
 
-	return nil, fmt.Errorf("unsupported type: %s", rt.Name())
+	return nil, fmt.Errorf("unsupported type: %s", rv.Type().Name())
 }
 
 // KeysE return the keys of map, sorted by asc
@@ -161,15 +161,20 @@ func KeysE(val interface{}) (sl []interface{}, err error) {
 		return nil, errUnsupportedTypeNil
 	}
 
-	_, rt, rv := indirect(val)
+	_, rv := indirect(val)
 
-	switch rt.Kind() {
+	switch rv.Kind() {
 	case reflect.Map:
 		for _, key := range sortedMapKeys(rv) {
 			sl = append(sl, key.Interface())
 		}
 		return
+		// case reflect.Struct:
+		// 	for _, v := range deepStructFields(rv.Type()) {
+		// 		sl = append(sl, v)
+		// 	}
+		// 	return
 	}
 
-	return nil, fmt.Errorf("unsupported type: %s", rt.Name())
+	return nil, fmt.Errorf("unsupported type: %s", rv.Type().Name())
 }

string.go

@@ -57,7 +57,7 @@ func StringE(val interface{}) (string, error) {
 	}
 
 	// indirect type
-	v, _, rv := indirect(val)
+	v, rv := indirect(val)
 	switch vv := v.(type) {
 	case nil:
 		return "", nil

time.go

@@ -20,7 +20,7 @@ func Time(v interface{}, def ...time.Time) time.Time {
 
 // TimeE convert an interface to a time.Time type
 func TimeE(val interface{}) (t time.Time, err error) {
-	v, _, _ := indirect(val)
+	v, _ := indirect(val)
 
 	// source type
 	switch vv := v.(type) {