fmt: fix lint issue

* Use unicode.ToUpper func to convert first letter in string to upper case
letter.

* Preallocate memory with correct length and cap because the final
  string is not changing.

README.md

@@ -6,7 +6,7 @@
 <div align="center" style="text-align: center;">
 
 ![Go version](https://img.shields.io/badge/go-%3E%3D1.16<recommend>-9cf)
-[![Release](https://img.shields.io/badge/release-1.0.10-green.svg)](https://github.com/duke-git/lancet/releases)
+[![Release](https://img.shields.io/badge/release-1.1.0-green.svg)](https://github.com/duke-git/lancet/releases)
 [![GoDoc](https://godoc.org/github.com//duke-git/lancet?status.svg)](https://pkg.go.dev/github.com/duke-git/lancet)
 [![Go Report Card](https://goreportcard.com/badge/github.com/duke-git/lancet)](https://goreportcard.com/report/github.com/duke-git/lancet)
 [![codecov](https://codecov.io/gh/duke-git/lancet/branch/main/graph/badge.svg?token=FC48T1F078)](https://codecov.io/gh/duke-git/lancet)
@@ -391,6 +391,7 @@ func Filter(slice, function interface{}) interface{} //filter slice, function si
 func Find(slice, function interface{}) interface{} //iterates over elements of slice, returning the first one that passes a truth test on function.function signature should be func(index int, value interface{}) bool .
 func IntSlice(slice interface{}) ([]int, error) //convert value to int slice
 func InterfaceSlice(slice interface{}) []interface{} //convert value to interface{} slice
+func Intersection(slices ...interface{}) interface{} //creates a slice of unique values that included by all slices.
 func InsertByIndex(slice interface{}, index int, value interface{}) (interface{}, error) //insert the element into slice at index.
 func Map(slice, function interface{}) interface{} //map lisce, function signature should be func(index int, value interface{}) interface{}
 func ReverseSlice(slice interface{}) //revere slice
@@ -399,7 +400,9 @@ func SortByField(slice interface{}, field string, sortType ...string) error //so
 func Some(slice, function interface{}) bool //return true if any of the values in the list pass the predicate function, function signature should be func(index int, value interface{}) bool
 func StringSlice(slice interface{}) []string //convert value to string slice
 func Unique(slice interface{}) interface{} //remove duplicate elements in slice
+func Union(slices ...interface{}) interface{} //Union creates a slice of unique values, in order, from all given slices. using == for equality comparisons.
 func UpdateByIndex(slice interface{}, index int, value interface{}) (interface{}, error) //update the slice element at index.
+func Without(slice interface{}, values ...interface{}) interface{} //creates a slice excluding all given values
 ```
 
 #### 10. strutil is for processing string

README_zh-CN.md

@@ -6,7 +6,7 @@
 <div align="center" style="text-align: center;">
 
 ![Go version](https://img.shields.io/badge/go-%3E%3D1.16<recommend>-9cf)
-[![Release](https://img.shields.io/badge/release-1.0.10-green.svg)](https://github.com/duke-git/lancet/releases)
+[![Release](https://img.shields.io/badge/release-1.1.0-green.svg)](https://github.com/duke-git/lancet/releases)
 [![GoDoc](https://godoc.org/github.com//duke-git/lancet?status.svg)](https://pkg.go.dev/github.com/duke-git/lancet)
 [![Go Report Card](https://goreportcard.com/badge/github.com/duke-git/lancet)](https://goreportcard.com/report/github.com/duke-git/lancet)
 [![codecov](https://codecov.io/gh/duke-git/lancet/branch/main/graph/badge.svg?token=FC48T1F078)](https://codecov.io/gh/duke-git/lancet)
@@ -392,6 +392,7 @@ func Find(slice, function interface{}) interface{} //查找slice中第一个符
 func Filter(slice, function interface{}) interface{} //过滤slice, 函数签名：func(index int, value interface{}) bool
 func IntSlice(slice interface{}) ([]int, error) //转成int切片
 func InterfaceSlice(slice interface{}) []interface{} //转成interface{}切片
+func Intersection(slices ...interface{}) interface{} //slice交集，去重
 func InsertByIndex(slice interface{}, index int, value interface{}) (interface{}, error) //在切片中index位置插入value
 func Map(slice, function interface{}) interface{} //遍历切片, 函数签名：func(index int, value interface{}) interface{}
 func ReverseSlice(slice interface{}) //反转切片
@@ -400,7 +401,9 @@ func Some(slice, function interface{}) bool //slice中任意一个元素都符
 func SortByField(slice interface{}, field string, sortType ...string) error //对struct切片进行排序
 func StringSlice(slice interface{}) []string //转为string切片
 func Unique(slice interface{}) interface{} //去重切片
+func Union(slices ...interface{}) interface{} //slice并集, 去重
 func UpdateByIndex(slice interface{}, index int, value interface{}) (interface{}, error) //在切片中index位置更新value
+func Without(slice interface{}, values ...interface{}) interface{} //slice去除values
 ```
 
 #### 10. strutil字符串处理包

fileutil/file_test.go

@@ -135,4 +135,4 @@ func TestReadFileByLine(t *testing.T) {
 	if !reflect.DeepEqual(res, expected) {
 		utils.LogFailedTestInfo(t, "ReadFileByLine", path, expected, res)
 	}
-}
+}

function/function.go

@@ -2,7 +2,6 @@
 // Use of this source code is governed by MIT license
 
 // Package function implements some functions for control the function execution and some is for functional programming.
-
 package function
 
 import (
@@ -36,10 +35,10 @@ func Before(n int, fn interface{}) func(args ...interface{}) []reflect.Value {
 		return res
 	}
 }
-
+// Fn is for curry function which is func(...interface{}) interface{}
 type Fn func(...interface{}) interface{}
 
-// Curry make a curryed function
+// Curry make a curry function
 func (f Fn) Curry(i interface{}) func(...interface{}) interface{} {
 	return func(values ...interface{}) interface{} {
 		v := append([]interface{}{i}, values...)
@@ -49,7 +48,7 @@ func (f Fn) Curry(i interface{}) func(...interface{}) interface{} {
 
 // Compose compose the functions from right to left
 func Compose(fnList ...func(...interface{}) interface{}) func(...interface{}) interface{} {
-	return func(s... interface{}) interface{} {
+	return func(s ...interface{}) interface{} {
 		f := fnList[0]
 		restFn := fnList[1:]
 
@@ -61,7 +60,6 @@ func Compose(fnList ...func(...interface{}) interface{}) func(...interface{}) in
 	}
 }
 
-
 // Delay make the function execution after delayed time
 func Delay(delay time.Duration, fn interface{}, args ...interface{}) {
 	time.Sleep(delay)

slice/slice.go

@@ -97,7 +97,7 @@ func Every(slice, function interface{}) bool {
 
 	elemType := sv.Type().Elem()
 	if checkSliceCallbackFuncSignature(fn, elemType, reflect.ValueOf(true).Type()) {
-		panic("Filter function must be of type func(int, " + elemType.String() + ")" + reflect.ValueOf(true).Type().String())
+		panic("function param should be of type func(int, " + elemType.String() + ")" + reflect.ValueOf(true).Type().String())
 	}
 
 	var indexes []int
@@ -119,7 +119,7 @@ func Some(slice, function interface{}) bool {
 
 	elemType := sv.Type().Elem()
 	if checkSliceCallbackFuncSignature(fn, elemType, reflect.ValueOf(true).Type()) {
-		panic("Filter function must be of type func(int, " + elemType.String() + ")" + reflect.ValueOf(true).Type().String())
+		panic("function param should be of type func(int, " + elemType.String() + ")" + reflect.ValueOf(true).Type().String())
 	}
 
 	has := false
@@ -141,7 +141,7 @@ func Filter(slice, function interface{}) interface{} {
 
 	elemType := sv.Type().Elem()
 	if checkSliceCallbackFuncSignature(fn, elemType, reflect.ValueOf(true).Type()) {
-		panic("Filter function must be of type func(int, " + elemType.String() + ")" + reflect.ValueOf(true).Type().String())
+		panic("function param should be of type func(int, " + elemType.String() + ")" + reflect.ValueOf(true).Type().String())
 	}
 
 	var indexes []int
@@ -167,7 +167,7 @@ func Find(slice, function interface{}) interface{} {
 
 	elemType := sv.Type().Elem()
 	if checkSliceCallbackFuncSignature(fn, elemType, reflect.ValueOf(true).Type()) {
-		panic("Filter function must be of type func(int, " + elemType.String() + ")" + reflect.ValueOf(true).Type().String())
+		panic("function param should be of type func(int, " + elemType.String() + ")" + reflect.ValueOf(true).Type().String())
 	}
 
 	var index int
@@ -189,7 +189,7 @@ func Map(slice, function interface{}) interface{} {
 
 	elemType := sv.Type().Elem()
 	if checkSliceCallbackFuncSignature(fn, elemType, nil) {
-		panic("Map function must be of type func(int, " + elemType.String() + ")" + elemType.String())
+		panic("function param should be of type func(int, " + elemType.String() + ")" + elemType.String())
 	}
 
 	res := reflect.MakeSlice(sv.Type(), sv.Len(), sv.Len())
@@ -215,7 +215,7 @@ func Reduce(slice, function, zero interface{}) interface{} {
 	fn := functionValue(function)
 	if checkSliceCallbackFuncSignature(fn, elementType, elementType, elementType) {
 		t := elementType.String()
-		panic("Reduce function must be of type func(int, " + t + ", " + t + ")" + t)
+		panic("function param should be of type func(int, " + t + ", " + t + ")" + t)
 	}
 
 	var params [3]reflect.Value
@@ -379,22 +379,28 @@ func Unique(slice interface{}) interface{} {
 		return slice
 	}
 
-	var res []interface{}
+	var temp []interface{}
+	len := 0
 	for i := 0; i < sv.Len(); i++ {
 		v := sv.Index(i).Interface()
-		flag := true
-		for j := range res {
-			if v == res[j] {
-				flag = false
+		skip := true
+		for j := range temp {
+			if v == temp[j] {
+				skip = false
 				break
 			}
 		}
-		if flag {
-			res = append(res, v)
+		if skip {
+			temp = append(temp, v)
+			len++
 		}
 	}
 
-	return res
+	res := reflect.MakeSlice(sv.Type(), len, len)
+	for i := 0; i < len; i++ {
+		res.Index(i).Set(reflect.ValueOf(temp[i]))
+	}
+	return res.Interface()
 
 	// if use map filter, the result slice element order is random, not same as origin slice
 	//mp := make(map[interface{}]bool)
@@ -411,6 +417,66 @@ func Unique(slice interface{}) interface{} {
 
 }
 
+// Union creates a slice of unique values, in order, from all given slices. using == for equality comparisons.
+func Union(slices ...interface{}) interface{} {
+	if len(slices) == 0 {
+		return nil
+	}
+	// append all slices, then unique it
+	var allSlice []interface{}
+	len := 0
+	for i := range slices {
+		sv := sliceValue(slices[i])
+		len += sv.Len()
+		for j := 0; j < sv.Len(); j++ {
+			v := sv.Index(j).Interface()
+			allSlice = append(allSlice, v)
+		}
+	}
+
+	sv := sliceValue(slices[0])
+	res := reflect.MakeSlice(sv.Type(), len, len)
+	for i := 0; i < len; i++ {
+		res.Index(i).Set(reflect.ValueOf(allSlice[i]))
+	}
+
+	return Unique(res.Interface())
+}
+
+// Intersection creates a slice of unique values that included by all slices.
+func Intersection(slices ...interface{}) interface{} {
+	if len(slices) == 0 {
+		return nil
+	}
+
+	reduceFunc := func(index int, slice1, slice2 interface{}) interface{} {
+		set := make([]interface{}, 0)
+		hash := make(map[interface{}]bool)
+
+		sv1 := reflect.ValueOf(slice1)
+		for i := 0; i < sv1.Len(); i++ {
+			v := sv1.Index(i).Interface()
+			hash[v] = true
+		}
+
+		sv2 := reflect.ValueOf(slice2)
+		for i := 0; i < sv2.Len(); i++ {
+			el := sv2.Index(i).Interface()
+			if _, found := hash[el]; found {
+				set = append(set, el)
+			}
+		}
+		res := reflect.MakeSlice(sv1.Type(), len(set), len(set))
+		for i := 0; i < len(set); i++ {
+			res.Index(i).Set(reflect.ValueOf(set[i]))
+		}
+		return res.Interface()
+	}
+
+	res := Reduce(slices, reduceFunc, nil)
+	return Union(res)
+}
+
 // ReverseSlice return slice of element order is reversed to the given slice
 func ReverseSlice(slice interface{}) {
 	v := sliceValue(slice)
@@ -474,3 +540,25 @@ func SortByField(slice interface{}, field string, sortType ...string) error {
 	}
 	return nil
 }
+
+// Without creates a slice excluding all given values
+func Without(slice interface{}, values ...interface{}) interface{} {
+	sv := sliceValue(slice)
+	if sv.Len() == 0 {
+		return slice
+	}
+	var indexes []int
+	for i := 0; i < sv.Len(); i++ {
+		v := sv.Index(i).Interface()
+		if !Contain(values, v) {
+			indexes = append(indexes, i)
+		}
+	}
+
+	res := reflect.MakeSlice(sv.Type(), len(indexes), len(indexes))
+	for i := range indexes {
+		res.Index(i).Set(sv.Index(indexes[i]))
+	}
+
+	return res.Interface()
+}

slice/slice_test.go

@@ -395,7 +395,7 @@ func updateByIndex(t *testing.T, test interface{}, index int, value, expected in
 func TestUnique(t *testing.T) {
 	t1 := []int{1, 2, 2, 3}
 	e1 := []int{1, 2, 3}
-	r1, _ := IntSlice(Unique(t1))
+	r1 := Unique(t1)
 	if !reflect.DeepEqual(r1, e1) {
 		utils.LogFailedTestInfo(t, "Unique", t1, e1, r1)
 		t.FailNow()
@@ -403,13 +403,60 @@ func TestUnique(t *testing.T) {
 
 	t2 := []string{"a", "a", "b", "c"}
 	e2 := []string{"a", "b", "c"}
-	r2 := StringSlice(Unique(t2))
+	r2 := Unique(t2)
 	if !reflect.DeepEqual(r2, e2) {
 		utils.LogFailedTestInfo(t, "Unique", t2, e2, r2)
 		t.FailNow()
 	}
 }
 
+func TestUnion(t *testing.T) {
+	s1 := []int{1, 3, 4, 6}
+	s2 := []int{1, 2, 5, 6}
+	s3 := []int{0, 4, 5, 7}
+
+	expected1 := []int{1, 3, 4, 6, 2, 5, 0, 7}
+	res1 := Union(s1, s2, s3)
+	if !reflect.DeepEqual(res1, expected1) {
+		utils.LogFailedTestInfo(t, "Union", s1, expected1, res1)
+		t.FailNow()
+	}
+
+	expected2 := []int{1, 3, 4, 6}
+	res2 := Union(s1)
+	if !reflect.DeepEqual(res2, expected2) {
+		utils.LogFailedTestInfo(t, "Union", s1, expected2, res2)
+		t.FailNow()
+	}
+}
+
+func TestIntersection(t *testing.T) {
+	s1 := []int{1, 2, 2, 3}
+	s2 := []int{1, 2, 3, 4}
+	s3 := []int{0, 2, 3, 5, 6}
+	s4 := []int{0, 5, 6}
+
+	expected := [][]int{
+		{2, 3},
+		{1, 2, 3},
+		{1, 2, 3},
+		{},
+	}
+	res := []interface{}{
+		Intersection(s1, s2, s3),
+		Intersection(s1, s2),
+		Intersection(s1),
+		Intersection(s1, s4),
+	}
+	for i := 0; i < len(res); i++ {
+		if !reflect.DeepEqual(res[i], expected[i]) {
+			utils.LogFailedTestInfo(t, "Intersection", "Intersection", expected[i], res[i])
+			t.FailNow()
+		}
+	}
+
+}
+
 func TestReverseSlice(t *testing.T) {
 	s1 := []int{1, 2, 3, 4, 5}
 	e1 := []int{5, 4, 3, 2, 1}
@@ -469,3 +516,14 @@ func TestSortByField(t *testing.T) {
 	}
 
 }
+
+func TestWithout(t *testing.T) {
+	s := []int{1, 2, 3, 4, 5}
+	expected := []int{3, 4, 5}
+	res := Without(s, 1, 2)
+
+	if !reflect.DeepEqual(res, expected) {
+		utils.LogFailedTestInfo(t, "Without", s, expected, res)
+		t.FailNow()
+	}
+}

strutil/string.go

@@ -7,6 +7,7 @@ package strutil
 import (
 	"regexp"
 	"strings"
+	"unicode"
 )
 
 // CamelCase covert string to camelCase string.
@@ -40,18 +41,16 @@ func Capitalize(s string) string {
 		return ""
 	}
 
-	res := ""
-	for i, v := range []rune(s) {
+	out := make([]rune, len(s))
+	for i, v := range s {
 		if i == 0 {
-			if v >= 97 && v <= 122 {
-				v -= 32
-			}
-			res += string(v)
+			out[i] = unicode.ToUpper(v)
 		} else {
-			res += strings.ToLower(string(v))
+			out[i] = unicode.ToLower(v)
 		}
 	}
-	return res
+
+	return string(out)
 }
 
 // LowerFirst converts the first character of string to lower case.