release v2.2.9

refactor: update StringToBytes logic
refactor:refactor random function (#164 )
2026-02-23 13:52:26 +08:00 · 2024-02-01 10:03:26 +08:00 · 2024-01-30 10:46:55 +08:00 · 2024-01-30 10:00:14 +08:00 · 2024-01-29 11:00:50 +08:00 · 2024-01-29 10:02:36 +08:00
26 changed files with 782 additions and 291 deletions
--- a/README.md
+++ b/README.md
@@ -4,7 +4,7 @@
 <br/>

 ![Go version](https://img.shields.io/badge/go-%3E%3Dv1.18-9cf)
-[![Release](https://img.shields.io/badge/release-2.2.8-green.svg)](https://github.com/duke-git/lancet/releases)
+[![Release](https://img.shields.io/badge/release-2.2.9-green.svg)](https://github.com/duke-git/lancet/releases)
 [![GoDoc](https://godoc.org/github.com/duke-git/lancet/v2?status.svg)](https://pkg.go.dev/github.com/duke-git/lancet/v2)
 [![Go Report Card](https://goreportcard.com/badge/github.com/duke-git/lancet/v2)](https://goreportcard.com/report/github.com/duke-git/lancet/v2)
 [![test](https://github.com/duke-git/lancet/actions/workflows/codecov.yml/badge.svg?branch=main&event=push)](https://github.com/duke-git/lancet/actions/workflows/codecov.yml)
@@ -706,6 +706,8 @@ import "github.com/duke-git/lancet/v2/fileutil"
    [[play](https://go.dev/play/p/OExTkhGEd3_u)]
 -   **<big>WriteCsvFile</big>** : write content to target csv file.
    [[doc](https://github.com/duke-git/lancet/blob/main/docs/en/api/packages/fileutil.md#WriteCsvFile)]
+-   **<big>WriteMapsToCsv</big>** : write slice of map to csv file.
+    [[doc](https://github.com/duke-git/lancet/blob/main/docs/en/api/packages/fileutil.md#WriteMapsToCsv)]
    [[play](https://go.dev/play/p/dAXm58Q5U1o)]
 -   **<big>WriteBytesToFile</big>** : write bytes to target file.
    [[doc](https://github.com/duke-git/lancet/blob/main/docs/en/api/packages/fileutil.md#WriteBytesToFile)]
@@ -1178,9 +1180,10 @@ import "github.com/duke-git/lancet/v2/slice"
 -   **<big>DifferenceWith</big>** : accepts comparator which is invoked to compare elements of slice to values.
    [[doc](https://github.com/duke-git/lancet/blob/main/docs/en/api/packages/slice.md#DifferenceWith)]
    [[play](https://go.dev/play/p/v2U2deugKuV)]
-   **<big>DeleteAt</big>** : delete the element of slice from specific start index to end index - 1.
+-   **<big>DeleteAt</big>** : delete the element of slice at index.
    [[doc](https://github.com/duke-git/lancet/blob/main/docs/en/api/packages/slice.md#DeleteAt)]
-    [[play](https://go.dev/play/p/pJ-d6MUWcvK)]
+-   **<big>DeleteRange</big>** : delete the element of slice from start index to end index（exclude).
+    [[doc](https://github.com/duke-git/lancet/blob/main/docs/en/api/packages/slice.md#DeleteRange)]
 -   **<big>Drop</big>** : drop n elements from the start of a slice.
    [[doc](https://github.com/duke-git/lancet/blob/main/docs/en/api/packages/slice.md#Drop)]
    [[play](https://go.dev/play/p/jnPO2yQsT8H)]
@@ -1942,22 +1945,6 @@ import "github.com/duke-git/lancet/v2/xerror"

 #### [Contributing Guide](./CONTRIBUTING.en-US.md)

-
-## Sponsor
-
-Hello, I am a software developer and have been engaged in development work for 13 years. Love open source software. And be willing to put in the energy for it. I am the creator of project lancet. Since Lancet was released as open source two years ago, it has been used by more than 1,000 internal and external projects. lancet will always be free for all users. Your support is a powerful encouragement for me to continue my struggle. Thanks! You can use WeChat to scans the following QR code or clicks the following sponsor button to initiate sponsorship.
-
-<div style="position: relative;display: inline-block;">
-    <img src="./docs/public/wechat_pay.png" width="260" height="260"/>
-    <a href="https://en.liberapay.com/Duke_Du/donate" target="\_blank"><img src="./docs/public/sponsor_btn.png" width="220" height="60"/></a>
-</div>
-
-<br/>
-<br/>
-
-*Donated funds will be used to maintain [lancet](https://www.golancet.cn/en/) website and pay for cloud server costs. Or just buy me a cup of ☕️ when I'm sleepy writing code.*
-
-
 ## Contributors
 Thank you to all the people who contributed to lancet!

--- a/README_zh-CN.md
+++ b/README_zh-CN.md
@@ -4,7 +4,7 @@
 <br/>

 ![Go version](https://img.shields.io/badge/go-%3E%3Dv1.18-9cf)
-[![Release](https://img.shields.io/badge/release-2.2.8-green.svg)](https://github.com/duke-git/lancet/releases)
+[![Release](https://img.shields.io/badge/release-2.2.9-green.svg)](https://github.com/duke-git/lancet/releases)
 [![GoDoc](https://godoc.org/github.com/duke-git/lancet/v2?status.svg)](https://pkg.go.dev/github.com/duke-git/lancet/v2)
 [![Go Report Card](https://goreportcard.com/badge/github.com/duke-git/lancet/v2)](https://goreportcard.com/report/github.com/duke-git/lancet/v2)
 [![test](https://github.com/duke-git/lancet/actions/workflows/codecov.yml/badge.svg?branch=main&event=push)](https://github.com/duke-git/lancet/actions/workflows/codecov.yml)
@@ -705,8 +705,10 @@ import "github.com/duke-git/lancet/v2/fileutil"
 -   **<big>ReadCsvFile</big>** : 读取 csv 文件内容到切片。
    [[doc](https://github.com/duke-git/lancet/blob/main/docs/api/packages/fileutil.md#ReadCsvFile)]
    [[play](https://go.dev/play/p/OExTkhGEd3_u)]
-   **<big>WriteCsvFile</big>** : 向 csv 文件写入内容。
+-   **<big>WriteCsvFile</big>** : 向csv文件写入切片数据。
    [[doc](https://github.com/duke-git/lancet/blob/main/docs/api/packages/fileutil.md#WriteCsvFile)]
+-   **<big>WriteMapsToCsv</big>** : 将map切片写入csv文件中。
+    [[doc](https://github.com/duke-git/lancet/blob/main/docs/api/packages/fileutil.md#WriteMapsToCsv)]
    [[play](https://go.dev/play/p/dAXm58Q5U1o)]
 -   **<big>WriteBytesToFile</big>** : 将 bytes 写入文件。
    [[doc](https://github.com/duke-git/lancet/blob/main/docs/api/packages/fileutil.md#WriteBytesToFile)]
@@ -1177,9 +1179,10 @@ import "github.com/duke-git/lancet/v2/slice"
 -   **<big>DifferenceWith</big>** : 接受比较器函数，该比较器被调用以将切片的元素与值进行比较。 结果值的顺序和引用由第一个切片确定。
    [[doc](https://github.com/duke-git/lancet/blob/main/docs/api/packages/slice.md#DifferenceWith)]
    [[play](https://go.dev/play/p/v2U2deugKuV)]
-   **<big>DeleteAt</big>** : 删除切片中指定开始索引到结束索引的元素。
+-   **<big>DeleteAt</big>** : 删除切片中指定索引到的元素。
    [[doc](https://github.com/duke-git/lancet/blob/main/docs/api/packages/slice.md#DeleteAt)]
-    [[play](https://go.dev/play/p/pJ-d6MUWcvK)]
+-   **<big>DeleteRange</big>** : 删除切片中指定开始索引到结束索引的元素。
+    [[doc](https://github.com/duke-git/lancet/blob/main/docs/api/packages/slice.md#DeleteRange)]
 -   **<big>Drop</big>** : 从切片头部删除 n 个元素。
    [[doc](https://github.com/duke-git/lancet/blob/main/docs/api/packages/slice.md#Drop)]
    [[play](https://go.dev/play/p/jnPO2yQsT8H)]
@@ -1943,23 +1946,9 @@ import "github.com/duke-git/lancet/v2/xerror"

 #### [贡献代码指南](./CONTRIBUTING.zh-CN.md)

-## 赞助
-
-您好，我是一名软件开发者，从事开发工作 13 年。热爱软件开源。并愿意为此付出精力。是开源项目 lancet 的作者。Lancet 自两年前开源发布以来，已有超过 1000 个内外部项目使用。lancet 一直会对所有用户免费。您的支持是对我继续奋斗的有力鼓励。谢谢! 微信扫描以下二维码或点击以下赞助按钮发起赞助。
-
-<div style="position: relative;display: inline-block;">
-    <img src="./docs/public/wechat_pay.png" width="260" height="260"/>
-    <a href="https://liberapay.com/Duke_Du/donate" target="\_blank"><img src="./docs/public/sponsor_btn.png" width="220" height="60"/></a>
-</div>
-
-<br/>
-<br/>
-
-_捐赠的资金将用于后续[lancet](https://www.golancet.cn/)官网的维护和云服务器的费用支付。或者当我写代码困倦时，给我买杯 ☕️。_
-
 ## 贡献者

-感谢所有为 lancet 贡献过代码的人！
+感谢所有为lancet贡献过代码的人！

 <a href="https://github.com/duke-git/lancet/graphs/contributors">
  <img src="https://contrib.rocks/image?repo=duke-git/lancet" />
--- a/datetime/datetime.go
+++ b/datetime/datetime.go
@@ -381,3 +381,12 @@ func TimestampNano(timezone ...string) int64 {

 	return t.UnixNano()
 }
+
+// TraceFuncTime: trace the func costed time,just call it at top of the func like `defer TraceFuncTime()()`
+func TraceFuncTime() func() {
+	pre := time.Now()
+	return func() {
+		elapsed := time.Since(pre)
+		fmt.Println("Costs Time:\t", elapsed)
+	}
+}
--- a/docs/api/packages/fileutil.md
+++ b/docs/api/packages/fileutil.md
@@ -45,6 +45,7 @@ import (
 -   [Sha](#Sha)
 -   [ReadCsvFile](#ReadCsvFile)
 -   [WriteCsvFile](#WriteCsvFile)
+-   [WriteMapsToCsv](#WriteMapsToCsv)
 -   [WriteStringToFile](#WriteStringToFile)
 -   [WriteBytesToFile](#WriteBytesToFile)
 -   [ReadFile](#ReadFile)
@@ -669,7 +670,7 @@ func main() {
 <b>函数签名:</b>

 ```go
-func ReadCsvFile(filepath string) ([][]string, error)
+func ReadCsvFile(filepath string, delimiter ...rune) ([][]string, error)
 ```

 <b>示例:<span style="float:right;display:inline-block;">[运行](https://go.dev/play/p/OExTkhGEd3_u)</span></b>
@@ -701,7 +702,7 @@ func main() {
 <b>函数签名:</b>

 ```go
-func WriteCsvFile(filepath string, records [][]string, append bool) error
+func WriteCsvFile(filepath string, records [][]string, append bool, delimiter ...rune) error
 ```

 <b>示例:<span style="float:right;display:inline-block;">[运行](https://go.dev/play/p/dAXm58Q5U1o)</span></b>
@@ -743,6 +744,59 @@ func main() {
 }
 ```

+### <span id="WriteMapsToCsv">WriteMapsToCsv</span>
+
+<p>将map切片写入csv文件中。</p>
+
+<b>函数签名:</b>
+
+```go
+// filepath: CSV文件路径。
+// records: 写入文件的map切片。map值必须为基本类型。会以map键的字母顺序写入。
+// appendToExistingFile: 是否为追加写模式。
+// delimiter: CSV文件分割符。
+// headers: CSV文件表头顺序（需要与map key保持一致)，不指定时按字母排序。
+func WriteMapsToCsv(filepath string, records []map[string]any, appendToExistingFile bool, delimiter rune, headers ...[]string) error
+```
+
+<b>示例:</b>
+
+```go
+package main
+
+import (
+    "fmt"
+    "github.com/duke-git/lancet/v2/fileutil"
+)
+
+func main() {
+    fpath := "./test.csv"
+    fileutil.CreateFile(fpath)
+
+    f, _ := os.OpenFile(fpath, os.O_WRONLY|os.O_TRUNC, 0777)
+    defer f.Close()
+
+    records := []map[string]any{
+        {"Name": "Lili", "Age": "22", "Gender": "female"},
+        {"Name": "Jim", "Age": "21", "Gender": "male"},
+    }
+
+    headers := []string{"Name", "Age", "Gender"}
+    err := WriteMapsToCsv(csvFilePath, records, false, ';', headers)
+
+    if err != nil {
+        log.Fatal(err)
+    }
+
+    content, err := fileutil.ReadCsvFile(csvFilePath, ';')
+
+    fmt.Println(content)
+
+    // Output:
+    // [[Name Age Gender] [Lili 22 female] [Jim 21 male]]
+}
+```
+
 ### <span id="WriteBytesToFile">WriteBytesToFile</span>

 <p>将bytes写入文件。</p>
--- a/docs/api/packages/slice.md
+++ b/docs/api/packages/slice.md
@@ -35,6 +35,7 @@ import (
 -   [DifferenceBy](#DifferenceBy)
 -   [DifferenceWith](#DifferenceWith)
 -   [DeleteAt](#DeleteAt)
+-   [DeleteRange](#DeleteRange)
 -   [Drop](#Drop)
 -   [DropRight](#DropRight)
 -   [DropWhile](#DropWhile)
@@ -516,12 +517,12 @@ func main() {

 ### <span id="DeleteAt">DeleteAt</span>

-<p>删除切片中指定开始索引到结束索引的元素</p>
+<p>删除切片中指定索引的元素（不修改原切片）。</p>

 <b>函数签名:</b>

 ```go
-func DeleteAt[T any](slice []T, start int, end ...int)
+func DeleteAt[T any](slice []T, index int) []T
 ```

 <b>示例:<span style="float:right;display:inline-block;">[运行](https://go.dev/play/p/pJ-d6MUWcvK)</span></b>
@@ -533,18 +534,66 @@ import (
 )

 func main() {
-    result1 := slice.DeleteAt([]string{"a", "b", "c"}, -1)
-    result2 := slice.DeleteAt([]string{"a", "b", "c"}, 0)
-    result3 := slice.DeleteAt([]string{"a", "b", "c"}, 0, 2)
+    chars := []string{"a", "b", "c", "d", "e"}
+
+    result1 := slice.DeleteAt(chars, 0)
+    result2 := slice.DeleteAt(chars, 4)
+    result3 := slice.DeleteAt(chars, 5)
+    result4 := slice.DeleteAt(chars, 6)

    fmt.Println(result1)
    fmt.Println(result2)
    fmt.Println(result3)
+    fmt.Println(result4)

    // Output:
-    // [a b c]
-    // [b c]
-    // [c]
+    // [b c d e]
+    // [a b c d]
+    // [a b c d]
+    // [a b c d]
+
+}
+```
+
+### <span id="DeleteRange">DeleteRange</span>
+
+<p>删除切片中指定索引范围的元素（不修改原切片）。</p>
+
+<b>函数签名:</b>
+
+```go
+func DeleteRange[T any](slice []T, start, end int) []T 
+```
+
+<b>示例:</b>
+
+```go
+import (
+    "fmt"
+    "github.com/duke-git/lancet/v2/slice"
+)
+
+func main() {
+    chars := []string{"a", "b", "c", "d", "e"}
+
+    result1 := DeleteRange(chars, 0, 0)
+    result2 := DeleteRange(chars, 0, 1)
+    result3 := DeleteRange(chars, 0, 3)
+    result4 := DeleteRange(chars, 0, 4)
+    result5 := DeleteRange(chars, 0, 5)
+
+    fmt.Println(result1)
+    fmt.Println(result2)
+    fmt.Println(result3)
+    fmt.Println(result4)
+    fmt.Println(result5)
+
+    // Output:
+    // [a b c d e]
+    // [b c d e]
+    // [d e]
+    // [e]
+    // []

 }
 ```
@@ -2475,18 +2524,18 @@ import (
 func main() {
    nums := []int{1, 2, 3, 4, 5}

-	result1 := slice.Partition(nums)
-	result2 := slice.Partition(nums, func(n int) bool { return n%2 == 0 })
-	result3 := slice.Partition(nums, func(n int) bool { return n == 1 || n == 2 }, func(n int) bool { return n == 2 || n == 3 || n == 4 })
+    result1 := slice.Partition(nums)
+    result2 := slice.Partition(nums, func(n int) bool { return n%2 == 0 })
+    result3 := slice.Partition(nums, func(n int) bool { return n == 1 || n == 2 }, func(n int) bool { return n == 2 || n == 3 || n == 4 })

-	fmt.Println(result1)
-	fmt.Println(result2)
-	fmt.Println(result3)
+    fmt.Println(result1)
+    fmt.Println(result2)
+    fmt.Println(result3)

-	// Output:
-	// [[1 2 3 4 5]]
-	// [[2 4] [1 3 5]]
-	// [[1 2] [3 4] [5]]
+    // Output:
+    // [[1 2 3 4 5]]
+    // [[2 4] [1 3 5]]
+    // [[1 2] [3 4] [5]]
 }
 ```

@@ -2510,13 +2559,13 @@ import (
 )

 func main() {
-	nums := []int{1, 2, 3, 4, 5}
+    nums := []int{1, 2, 3, 4, 5}

-	val, idx := slice.Random(nums)
-	if idx >= 0 && idx < len(nums) && slice.Contain(nums, val) {
-		fmt.Println("okk")
-	}
-	// Output:
-	// okk
+    val, idx := slice.Random(nums)
+    if idx >= 0 && idx < len(nums) && slice.Contain(nums, val) {
+        fmt.Println("okk")
+    }
+    // Output:
+    // okk
 }
 ```
--- a/docs/en/api/packages/fileutil.md
+++ b/docs/en/api/packages/fileutil.md
@@ -45,6 +45,8 @@ import (
 -   [Sha](#Sha)
 -   [ReadCsvFile](#ReadCsvFile)
 -   [WriteCsvFile](#WriteCsvFile)
+-   [WriteCsvFile](#WriteCsvFile)
+-   [WriteMapsToCsv](#WriteMapsToCsv)
 -   [WriteStringToFile](#WriteStringToFile)
 -   [WriteBytesToFile](#WriteBytesToFile)
 -   [ReadFile](#ReadFile)
@@ -669,7 +671,7 @@ func main() {
 <b>Signature:</b>

 ```go
-func ReadCsvFile(filepath string) ([][]string, error)
+func ReadCsvFile(filepath string, delimiter ...rune) ([][]string, error)
 ```

 <b>Example:<span style="float:right;display:inline-block;">[Run](https://go.dev/play/p/OExTkhGEd3_u)</span></b>
@@ -701,7 +703,7 @@ func main() {
 <b>Signature:</b>

 ```go
-func WriteCsvFile(filepath string, records [][]string, append bool) error
+func WriteCsvFile(filepath string, records [][]string, append bool, delimiter ...rune) error
 ```

 <b>Example:<span style="float:right;display:inline-block;">[Run](https://go.dev/play/p/dAXm58Q5U1o)</span></b>
@@ -743,6 +745,59 @@ func main() {
 }
 ```

+### <span id="WriteMapsToCsv">WriteMapsToCsv</span>
+
+<p>Write slice of map to csv file.</p>
+
+<b>Signature:</b>
+
+```go
+// filepath: path of the CSV file.
+// records: slice of maps to be written. the value of map should be basic type. The maps will be sorted by key in alphabeta order, then be written into csv file.
+// appendToExistingFile: If true, data will be appended to the file if it exists.
+// delimiter: Delimiter to use in the CSV file.
+// headers: order of the csv column headers, needs to be consistent with the key of the map.
+func WriteMapsToCsv(filepath string, records []map[string]any, appendToExistingFile bool, delimiter rune, headers ...[]string) error
+```
+
+<b>Example:</b>
+
+```go
+package main
+
+import (
+    "fmt"
+    "github.com/duke-git/lancet/v2/fileutil"
+)
+
+func main() {
+    fpath := "./test.csv"
+    fileutil.CreateFile(fpath)
+
+    f, _ := os.OpenFile(fpath, os.O_WRONLY|os.O_TRUNC, 0777)
+    defer f.Close()
+
+    records := []map[string]any{
+        {"Name": "Lili", "Age": "22", "Gender": "female"},
+        {"Name": "Jim", "Age": "21", "Gender": "male"},
+    }
+
+    headers := []string{"Name", "Age", "Gender"}
+    err := fileutil.WriteMapsToCsv(csvFilePath, records, false, ';', headers)
+
+    if err != nil {
+        log.Fatal(err)
+    }
+
+    content, err := fileutil.ReadCsvFile(csvFilePath, ';')
+
+    fmt.Println(content)
+
+    // Output:
+    // [[Name Age Gender] [Lili 22 female] [Jim 21 male]]
+}
+```
+
 ### <span id="WriteBytesToFile">WriteBytesToFile</span>

 <p>Writes bytes to target file.</p>
--- a/docs/en/api/packages/slice.md
+++ b/docs/en/api/packages/slice.md
@@ -35,6 +35,7 @@ import (
 -   [DifferenceBy](#DifferenceBy)
 -   [DifferenceWith](#DifferenceWith)
 -   [DeleteAt](#DeleteAt)
+-   [DeleteRange](#DeleteRange)
 -   [Drop](#Drop)
 -   [DropRight](#DropRight)
 -   [DropWhile](#DropWhile)
@@ -515,12 +516,12 @@ func main() {

 ### <span id="DeleteAt">DeleteAt</span>

-<p>Delete the element of slice from start index to end index - 1.</p>
+<p>Delete delete the element of slice at index.</p>

 <b>Signature:</b>

 ```go
-func DeleteAt[T any](slice []T, start int, end ...int)
+func DeleteAt[T any](slice []T, index int)
 ```

 <b>Example:<span style="float:right;display:inline-block;">[Run](https://go.dev/play/p/pJ-d6MUWcvK)</span></b>
@@ -532,18 +533,66 @@ import (
 )

 func main() {
-    result1 := slice.DeleteAt([]string{"a", "b", "c"}, -1)
-    result2 := slice.DeleteAt([]string{"a", "b", "c"}, 0)
-    result3 := slice.DeleteAt([]string{"a", "b", "c"}, 0, 2)
+    chars := []string{"a", "b", "c", "d", "e"}
+
+    result1 := slice.DeleteAt(chars, 0)
+    result2 := slice.DeleteAt(chars, 4)
+    result3 := slice.DeleteAt(chars, 5)
+    result4 := slice.DeleteAt(chars, 6)

    fmt.Println(result1)
    fmt.Println(result2)
    fmt.Println(result3)
+    fmt.Println(result4)

    // Output:
-    // [a b c]
-    // [b c]
-    // [c]
+    // [b c d e]
+    // [a b c d]
+    // [a b c d]
+    // [a b c d]
+}
+```
+
+### <span id="DeleteRange">DeleteRange</span>
+
+<p>Delete the element of slice from start index to end index（exclude)</p>
+
+<b>Signature:</b>
+
+```go
+func DeleteRange[T any](slice []T, start, end int) []T 
+```
+
+<b>Example:</b>
+
+```go
+import (
+    "fmt"
+    "github.com/duke-git/lancet/v2/slice"
+)
+
+func main() {
+    chars := []string{"a", "b", "c", "d", "e"}
+
+    result1 := DeleteRange(chars, 0, 0)
+    result2 := DeleteRange(chars, 0, 1)
+    result3 := DeleteRange(chars, 0, 3)
+    result4 := DeleteRange(chars, 0, 4)
+    result5 := DeleteRange(chars, 0, 5)
+
+    fmt.Println(result1)
+    fmt.Println(result2)
+    fmt.Println(result3)
+    fmt.Println(result4)
+    fmt.Println(result5)
+
+    // Output:
+    // [a b c d e]
+    // [b c d e]
+    // [d e]
+    // [e]
+    // []
+
 }
 ```

@@ -2473,18 +2522,18 @@ import (
 func main() {
    nums := []int{1, 2, 3, 4, 5}

-	result1 := slice.Partition(nums)
-	result2 := slice.Partition(nums, func(n int) bool { return n%2 == 0 })
-	result3 := slice.Partition(nums, func(n int) bool { return n == 1 || n == 2 }, func(n int) bool { return n == 2 || n == 3 || n == 4 })
+    result1 := slice.Partition(nums)
+    result2 := slice.Partition(nums, func(n int) bool { return n%2 == 0 })
+    result3 := slice.Partition(nums, func(n int) bool { return n == 1 || n == 2 }, func(n int) bool { return n == 2 || n == 3 || n == 4 })

-	fmt.Println(result1)
-	fmt.Println(result2)
-	fmt.Println(result3)
+    fmt.Println(result1)
+    fmt.Println(result2)
+    fmt.Println(result3)

-	// Output:
-	// [[1 2 3 4 5]]
-	// [[2 4] [1 3 5]]
-	// [[1 2] [3 4] [5]]
+    // Output:
+    // [[1 2 3 4 5]]
+    // [[2 4] [1 3 5]]
+    // [[1 2] [3 4] [5]]
 }
 ```

@@ -2507,13 +2556,13 @@ import (
 )

 func main() {
-	nums := []int{1, 2, 3, 4, 5}
+    nums := []int{1, 2, 3, 4, 5}

-	val, idx := slice.Random(nums)
-	if idx >= 0 && idx < len(nums) && slice.Contain(nums, val) {
-		fmt.Println("okk")
-	}
-	// Output:
-	// okk
+    val, idx := slice.Random(nums)
+    if idx >= 0 && idx < len(nums) && slice.Contain(nums, val) {
+        fmt.Println("okk")
+    }
+    // Output:
+    // okk
 }
 ```
--- a/fileutil/file.go
+++ b/fileutil/file.go
@@ -20,11 +20,67 @@ import (
 	"os"
 	"path/filepath"
 	"runtime"
+	"sort"
 	"strings"

 	"github.com/duke-git/lancet/v2/validator"
 )

+// FileReader is a reader supporting offset seeking and reading one
+// line at a time, this is especially useful for large files
+type FileReader struct {
+	*bufio.Reader
+	file   *os.File
+	offset int64
+}
+
+// NewFileReader creates the FileReader struct for reading
+func NewFileReader(path string) (*FileReader, error) {
+	f, err := os.Open(path)
+	if err != nil {
+		return nil, err
+	}
+	return &FileReader{
+		file:   f,
+		Reader: bufio.NewReader(f),
+		offset: 0,
+	}, nil
+}
+
+// ReadLine reads and returns one line at a time excluding the trailing '\r' and '\n'
+func (f *FileReader) ReadLine() (string, error) {
+	data, err := f.Reader.ReadBytes('\n')
+	f.offset += int64(len(data))
+	if err == nil || err == io.EOF {
+		for len(data) > 0 && (data[len(data)-1] == '\r' || data[len(data)-1] == '\n') {
+			data = data[:len(data)-1]
+		}
+		return string(data), err
+	}
+	return "", err
+}
+
+// Offset returns the current offset of the file
+func (f *FileReader) Offset() int64 {
+	return f.offset
+}
+
+// Seek sets the current offset of the reading
+func (f *FileReader) Seek(offset int64) error {
+	_, err := f.file.Seek(offset, 0)
+	if err != nil {
+		return err
+	}
+	f.Reader = bufio.NewReader(f.file)
+	f.offset = offset
+	return nil
+}
+
+// Close takes care of the opened file
+func (f *FileReader) Close() error {
+	return f.file.Close()
+}
+
 // IsExist checks if a file or directory exists.
 // Play: https://go.dev/play/p/nKKXt8ZQbmh
 func IsExist(path string) bool {
@@ -508,6 +564,25 @@ func FileSize(path string) (int64, error) {
 	return f.Size(), nil
 }

+// DirSize walks the folder recursively and returns folder size in bytes.
+func DirSize(path string) (int64, error) {
+	var size int64
+	err := filepath.WalkDir(path, func(_ string, d os.DirEntry, err error) error {
+		if err != nil {
+			return err
+		}
+		if !d.IsDir() {
+			info, err := d.Info()
+			if err != nil {
+				return err
+			}
+			size += info.Size()
+		}
+		return err
+	})
+	return size, err
+}
+
 // MTime returns file modified time.
 // Play: https://go.dev/play/p/s_Tl7lZoAaY
 func MTime(filepath string) (int64, error) {
@@ -536,7 +611,7 @@ func Sha(filepath string, shaType ...int) (string, error) {
 		} else if shaType[0] == 512 {
 			h = sha512.New()
 		} else {
-			return "", errors.New("param `shaType` should be 1, 256 or 512.")
+			return "", errors.New("param `shaType` should be 1, 256 or 512")
 		}
 	}

@@ -554,15 +629,19 @@ func Sha(filepath string, shaType ...int) (string, error) {

 // ReadCsvFile read file content into slice.
 // Play: https://go.dev/play/p/OExTkhGEd3_u
-func ReadCsvFile(filepath string) ([][]string, error) {
+func ReadCsvFile(filepath string, delimiter ...rune) ([][]string, error) {
 	f, err := os.Open(filepath)
 	if err != nil {
 		return nil, err
 	}
 	defer f.Close()

-	csvReader := csv.NewReader(f)
-	records, err := csvReader.ReadAll()
+	reader := csv.NewReader(f)
+	if len(delimiter) > 0 {
+		reader.Comma = delimiter[0]
+	}
+
+	records, err := reader.ReadAll()
 	if err != nil {
 		return nil, err
 	}
@@ -571,8 +650,10 @@ func ReadCsvFile(filepath string) ([][]string, error) {
 }

 // WriteCsvFile write content to target csv file.
+// append: append to existing csv file
+// delimiter: specifies csv delimiter
 // Play: https://go.dev/play/p/dAXm58Q5U1o
-func WriteCsvFile(filepath string, records [][]string, append bool) error {
+func WriteCsvFile(filepath string, records [][]string, append bool, delimiter ...rune) error {
 	flag := os.O_RDWR | os.O_CREATE

 	if append {
@@ -587,7 +668,19 @@ func WriteCsvFile(filepath string, records [][]string, append bool) error {
 	defer f.Close()

 	writer := csv.NewWriter(f)
-	writer.Comma = ','
+	// 设置默认分隔符为逗号，除非另外指定
+	if len(delimiter) > 0 {
+		writer.Comma = delimiter[0]
+	} else {
+		writer.Comma = ','
+	}
+
+	// 遍历所有记录并处理包含分隔符或双引号的单元格
+	for i := range records {
+		for j := range records[i] {
+			records[i][j] = escapeCSVField(records[i][j], writer.Comma)
+		}
+	}

 	return writer.WriteAll(records)
 }
@@ -646,3 +739,71 @@ func ReadFile(path string) (reader io.ReadCloser, closeFn func(), err error) {
 		return nil, func() {}, errors.New("unknown file type")
 	}
 }
+
+// escapeCSVField 处理单元格内容，如果包含分隔符，则用双引号包裹
+func escapeCSVField(field string, delimiter rune) string {
+	// 替换所有的双引号为两个双引号
+	escapedField := strings.ReplaceAll(field, "\"", "\"\"")
+
+	// 如果字段包含分隔符、双引号或换行符，用双引号包裹整个字段
+	if strings.ContainsAny(escapedField, string(delimiter)+"\"\n") {
+		escapedField = fmt.Sprintf("\"%s\"", escapedField)
+	}
+
+	return escapedField
+}
+
+// WriteMapsToCsv write slice of map to csv file.
+// Play: todo
+// filepath: Path to the CSV file.
+// records: Slice of maps to be written. the value of map should be basic type.
+// the maps will be sorted by key in alphabeta order, then be written into csv file.
+// appendToExistingFile: If true, data will be appended to the file if it exists.
+// delimiter: Delimiter to use in the CSV file.
+// headers: order of the csv column headers, needs to be consistent with the key of the map.
+func WriteMapsToCsv(filepath string, records []map[string]any, appendToExistingFile bool, delimiter rune,
+	headers ...[]string) error {
+	for _, record := range records {
+		for _, value := range record {
+			if !isCsvSupportedType(value) {
+				return errors.New("unsupported value type detected; only basic types are supported: \nbool, rune, string, int, int64, float32, float64, uint, byte, complex128, complex64, uintptr")
+			}
+		}
+	}
+
+	var columnHeaders []string
+	if len(headers) > 0 {
+		columnHeaders = headers[0]
+	} else {
+		for key := range records[0] {
+			columnHeaders = append(columnHeaders, key)
+		}
+		// sort keys in alphabeta order
+		sort.Strings(columnHeaders)
+	}
+
+	var datasToWrite [][]string
+	if !appendToExistingFile {
+		datasToWrite = append(datasToWrite, columnHeaders)
+	}
+
+	for _, record := range records {
+		var row []string
+		for _, h := range columnHeaders {
+			row = append(row, fmt.Sprintf("%v", record[h]))
+		}
+		datasToWrite = append(datasToWrite, row)
+	}
+
+	return WriteCsvFile(filepath, datasToWrite, appendToExistingFile, delimiter)
+}
+
+// check if the value of map which to be written into csv is basic type.
+func isCsvSupportedType(v interface{}) bool {
+	switch v.(type) {
+	case bool, rune, string, int, int64, float32, float64, uint, byte, complex128, complex64, uintptr:
+		return true
+	default:
+		return false
+	}
+}
--- a/fileutil/file_example_test.go
+++ b/fileutil/file_example_test.go
@@ -3,6 +3,7 @@ package fileutil
 import (
 	"fmt"
 	"io"
+	"log"
 	"os"
 )

@@ -331,6 +332,28 @@ func ExampleWriteCsvFile() {
 	// [[Lili 22 female] [Jim 21 male]]
 }

+func ExampleWriteMapsToCsv() {
+	csvFilePath := "./testdata/test3.csv"
+	records := []map[string]any{
+		{"Name": "Lili", "Age": "22", "Gender": "female"},
+		{"Name": "Jim", "Age": "21", "Gender": "male"},
+	}
+
+	headers := []string{"Name", "Age", "Gender"}
+	err := WriteMapsToCsv(csvFilePath, records, false, ';', headers)
+
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	content, err := ReadCsvFile(csvFilePath, ';')
+
+	fmt.Println(content)
+
+	// Output:
+	// [[Name Age Gender] [Lili 22 female] [Jim 21 male]]
+}
+
 func ExampleWriteStringToFile() {
 	filepath := "./test.txt"

--- a/fileutil/file_test.go
+++ b/fileutil/file_test.go
@@ -340,10 +340,14 @@ func TestSha(t *testing.T) {
 	assert := internal.NewAssert(t, "TestSha")

 	sha1, err := Sha("./testdata/test.txt", 1)
-	sha256, err := Sha("./testdata/test.txt", 256)
-	sha512, err := Sha("./testdata/test.txt", 512)
-
 	assert.IsNil(err)
+
+	sha256, err := Sha("./testdata/test.txt", 256)
+	assert.IsNil(err)
+
+	sha512, err := Sha("./testdata/test.txt", 512)
+	assert.IsNil(err)
+
 	assert.Equal("dda3cf10c5a6ff6c6659a497bf7261b287af2bc7", sha1)
 	assert.Equal("aa6d0a3fbc3442c228d606da09e0c1dc98c69a1cac3da1909199e0266171df35", sha256)
 	assert.Equal("d22aba2a1b7a2e2f512756255cc1c3708905646920cb1eb95e45b531ba74774dbbb89baebf1f716220eb9cf4908f1cfc5b2a01267704d9a59f59d77cab609870", sha512)
@@ -379,11 +383,36 @@ func TestWriteCsvFile(t *testing.T) {

 	assert.Equal(2, len(readContent))
 	assert.Equal(3, len(readContent[0]))
-	assert.Equal("Lili", content[0][0])
+	assert.Equal("Lili", readContent[0][0])

 	// RemoveFile(csvFilePath)
 }

+func TestWriteMapsToCsv(t *testing.T) {
+	assert := internal.NewAssert(t, "TestWriteMapsToCSV")
+
+	csvFilePath := "./testdata/test4.csv"
+	records := []map[string]any{
+		{"Name": "Lili", "Age": "22", "Gender": "female"},
+		{"Name": "Jim", "Age": "21", "Gender": "male"},
+	}
+
+	headers := []string{"Name", "Age", "Gender"}
+	err := WriteMapsToCsv(csvFilePath, records, false, ';', headers)
+
+	assert.IsNil(err)
+
+	content, err := ReadCsvFile(csvFilePath, ';')
+
+	assert.IsNil(err)
+
+	assert.Equal(3, len(content))
+	assert.Equal(3, len(content[0]))
+	assert.Equal("Lili", content[1][0])
+	assert.Equal("22", content[1][1])
+	assert.Equal("female", content[1][2])
+}
+
 func TestWriteStringToFile(t *testing.T) {
 	assert := internal.NewAssert(t, "TestWriteStringToFile")

@@ -476,3 +505,42 @@ Disallow: /deny
 `
 	internal.NewAssert(t, "TestReadFile").Equal(want, string(dat))
 }
+
+func TestReadlineFile(t *testing.T) {
+	path := "./testdata/demo.csv"
+	reader, err := NewFileReader(path)
+	if err != nil {
+		t.Fail()
+	}
+	defer reader.Close()
+
+	indexMap := make(map[string]int64)
+	defer reader.Close()
+	for {
+		offset := reader.Offset()
+		line, err := reader.ReadLine()
+		if err == io.EOF {
+			break
+		}
+		indexMap[line] = offset
+	}
+
+	lines, err := ReadFileByLine(path)
+	if err != nil {
+		t.Fail()
+	}
+	for _, line := range lines {
+		offset, ok := indexMap[line]
+		if !ok {
+			t.Fail()
+		}
+		if err = reader.Seek(offset); err != nil {
+			t.Fail()
+		}
+		lineRead, err := reader.ReadLine()
+		if err == io.EOF {
+			break
+		}
+		internal.NewAssert(t, "TestReadlineFile").Equal(line, lineRead)
+	}
+}
--- a/fileutil/testdata/test1.csv
+++ b/fileutil/testdata/test1.csv
@@ -1,3 +1,5 @@
 Lili,22,female
 Jim,21,male

+
+
--- a/fileutil/testdata/test2.csv
+++ b/fileutil/testdata/test2.csv
@@ -1,3 +1,5 @@
 Lili,22,female
 Jim,21,male

+
+
--- a/fileutil/testdata/test3.csv
+++ b/fileutil/testdata/test3.csv
@@ -0,0 +1,3 @@
+Name;Age;Gender
+Lili;22;female
+Jim;21;male
--- a/fileutil/testdata/test4.csv
+++ b/fileutil/testdata/test4.csv
@@ -0,0 +1,3 @@
+Name;Age;Gender
+Lili;22;female
+Jim;21;male
--- a/formatter/formatter.go
+++ b/formatter/formatter.go
@@ -6,12 +6,11 @@ package formatter

 import (
 	"encoding/json"
-	"fmt"
 	"io"
+	"strconv"
+	"strings"

 	"github.com/duke-git/lancet/v2/convertor"
-	"github.com/duke-git/lancet/v2/strutil"
-	"github.com/duke-git/lancet/v2/validator"
 	"golang.org/x/exp/constraints"
 )

@@ -20,31 +19,24 @@ import (
 // Comma("12345", "$") => "$12,345", Comma(12345, "$") => "$12,345"
 // Play: https://go.dev/play/p/eRD5k2vzUVX
 func Comma[T constraints.Float | constraints.Integer | string](value T, symbol string) string {
-	if validator.IsInt(value) {
-		v, err := convertor.ToInt(value)
-		if err != nil {
-			return ""
-		}
-		return symbol + commaInt(v)
-	}
+	numString := convertor.ToString(value)

-	if validator.IsFloat(value) {
-		v, err := convertor.ToFloat(value)
-		if err != nil {
-			return ""
-		}
-		return symbol + commaFloat(v)
-	}
-
-	if strutil.IsString(value) {
-		v := fmt.Sprintf("%v", value)
-		if validator.IsNumberStr(v) {
-			return symbol + commaStr(v)
-		}
+	_, err := strconv.ParseFloat(numString, 64)
+	if err != nil {
 		return ""
 	}

-	return ""
+	index := strings.Index(numString, ".")
+	if index == -1 {
+		index = len(numString)
+	}
+
+	for index > 3 {
+		index = index - 3
+		numString = numString[:index] + "," + numString[index:]
+	}
+
+	return symbol + numString
 }

 // Pretty data to JSON string.
--- a/formatter/formatter_internal.go
+++ b/formatter/formatter_internal.go
@@ -1,85 +0,0 @@
-package formatter
-
-import (
-	"bytes"
-	"math"
-	"strconv"
-	"strings"
-)
-
-// see https://github.com/dustin/go-humanize/blob/master/comma.go
-func commaInt(v int64) string {
-	sign := ""
-
-	// Min int64 can't be negated to a usable value, so it has to be special cased.
-	if v == math.MinInt64 {
-		return "-9,223,372,036,854,775,808"
-	}
-
-	if v < 0 {
-		sign = "-"
-		v = 0 - v
-	}
-
-	parts := []string{"", "", "", "", "", "", ""}
-	j := len(parts) - 1
-
-	for v > 999 {
-		parts[j] = strconv.FormatInt(v%1000, 10)
-		switch len(parts[j]) {
-		case 2:
-			parts[j] = "0" + parts[j]
-		case 1:
-			parts[j] = "00" + parts[j]
-		}
-		v = v / 1000
-		j--
-	}
-	parts[j] = strconv.Itoa(int(v))
-	return sign + strings.Join(parts[j:], ",")
-}
-
-func commaFloat(v float64) string {
-	buf := &bytes.Buffer{}
-	if v < 0 {
-		buf.Write([]byte{'-'})
-		v = 0 - v
-	}
-
-	comma := []byte{','}
-
-	parts := strings.Split(strconv.FormatFloat(v, 'f', -1, 64), ".")
-	pos := 0
-	if len(parts[0])%3 != 0 {
-		pos += len(parts[0]) % 3
-		buf.WriteString(parts[0][:pos])
-		buf.Write(comma)
-	}
-	for ; pos < len(parts[0]); pos += 3 {
-		buf.WriteString(parts[0][pos : pos+3])
-		buf.Write(comma)
-	}
-	buf.Truncate(buf.Len() - 1)
-
-	if len(parts) > 1 {
-		buf.Write([]byte{'.'})
-		buf.WriteString(parts[1])
-	}
-	return buf.String()
-}
-
-func commaStr(s string) string {
-	dotIndex := strings.Index(s, ".")
-	if dotIndex != -1 {
-		return commaStrRecursive(s[:dotIndex]) + s[dotIndex:]
-	}
-
-	return commaStrRecursive(s)
-}
-
-func commaStrRecursive(s string) string {
-	if len(s) <= 3 {
-		return s
-	}
-	return commaStrRecursive(s[:len(s)-3]) + "," + commaStrRecursive(s[len(s)-3:])
-}
--- a/pointer/pointer.go
+++ b/pointer/pointer.go
@@ -4,7 +4,9 @@
 // Package pointer contains some util functions to operate go pointer.
 package pointer

-import "reflect"
+import (
+	"reflect"
+)

 // Of returns a pointer to the value `v`.
 // Play: https://go.dev/play/p/HFd70x4DrMj
@@ -47,5 +49,10 @@ func ExtractPointer(value any) any {
 	if t.Kind() != reflect.Pointer {
 		return value
 	}
-	return ExtractPointer(v.Elem().Interface())
+
+	if v.Elem().IsValid() {
+		return ExtractPointer(v.Elem().Interface())
+	}
+
+	return nil
 }
--- a/random/random.go
+++ b/random/random.go
@@ -8,20 +8,25 @@ import (
 	crand "crypto/rand"
 	"fmt"
 	"io"
+	"math"
 	"math/rand"
 	"time"
+	"unsafe"

 	"github.com/duke-git/lancet/v2/mathutil"
 )

 const (
-	Numeral       = "0123456789"
-	LowwerLetters = "abcdefghijklmnopqrstuvwxyz"
-	UpperLetters  = "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
-	Letters       = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ"
-	SymbolChars   = "!@#$%^&*()_+-=[]{}|;':\",./<>?"
+	MaximumCapacity = 1 << 31
+	Numeral         = "0123456789"
+	LowwerLetters   = "abcdefghijklmnopqrstuvwxyz"
+	UpperLetters    = "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
+	Letters         = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ"
+	SymbolChars     = "!@#$%^&*()_+-=[]{}|;':\",./<>?"
 )

+var rn = rand.NewSource(time.Now().UnixNano())
+
 func init() {
 	rand.Seed(time.Now().UnixNano())
 }
@@ -108,18 +113,61 @@ func RandSymbolChar(length int) string {
 	return random(SymbolChars, length)
 }

+// nearestPowerOfTwo 返回一个大于等于cap的最近的2的整数次幂，参考java8的hashmap的tableSizeFor函数
+func nearestPowerOfTwo(cap int) int {
+	n := cap - 1
+	n |= n >> 1
+	n |= n >> 2
+	n |= n >> 4
+	n |= n >> 8
+	n |= n >> 16
+	if n < 0 {
+		return 1
+	} else if n >= MaximumCapacity {
+		return MaximumCapacity
+	}
+	return n + 1
+}
+
 // random generate a random string based on given string range.
 func random(s string, length int) string {
-	b := make([]byte, length)
-
-	// fix: https://github.com/duke-git/lancet/issues/75
-	// r := rand.New(rand.NewSource(time.Now().UnixNano()))
-
-	for i := range b {
-		b[i] = s[rand.Int63()%int64(len(s))]
+	// 仿照strings.Builder
+	// 创建一个长度为 length 的字节切片
+	bytes := make([]byte, length)
+	strLength := len(s)
+	if strLength <= 0 {
+		return ""
+	} else if strLength == 1 {
+		for i := 0; i < length; i++ {
+			bytes[i] = s[0]
+		}
+		return *(*string)(unsafe.Pointer(&bytes))
 	}
-
-	return string(b)
+	// s的字符需要使用多少个比特位数才能表示完
+	// letterIdBits := int(math.Ceil(math.Log2(strLength))),下面比上面的代码快
+	letterIdBits := int(math.Log2(float64(nearestPowerOfTwo(strLength))))
+	// 最大的字母id掩码
+	var letterIdMask int64 = 1<<letterIdBits - 1
+	// 可用次数的最大值
+	letterIdMax := 63 / letterIdBits
+	// 循环生成随机字符串
+	for i, cache, remain := length-1, rn.Int63(), letterIdMax; i >= 0; {
+		// 检查随机数生成器是否用尽所有随机数
+		if remain == 0 {
+			cache, remain = rn.Int63(), letterIdMax
+		}
+		// 从可用字符的字符串中随机选择一个字符
+		if idx := int(cache & letterIdMask); idx < len(s) {
+			bytes[i] = s[idx]
+			i--
+		}
+		// 右移比特位数，为下次选择字符做准备
+		cache >>= letterIdBits
+		remain--
+	}
+	// 仿照strings.Builder用unsafe包返回一个字符串，避免拷贝
+	// 将字节切片转换为字符串并返回
+	return *(*string)(unsafe.Pointer(&bytes))
 }

 // UUIdV4 generate a random UUID of version 4 according to RFC 4122.
--- a/slice/slice.go
+++ b/slice/slice.go
@@ -498,20 +498,13 @@ func FlatMap[T any, U any](slice []T, iteratee func(index int, item T) []U) []U
 // Reduce creates an slice of values by running each element of slice thru iteratee function.
 // Play: https://go.dev/play/p/_RfXJJWIsIm
 func Reduce[T any](slice []T, iteratee func(index int, item1, item2 T) T, initial T) T {
-	if len(slice) == 0 {
-		return initial
+	accumulator := initial
+
+	for i, v := range slice {
+		accumulator = iteratee(i, v, accumulator)
 	}

-	result := iteratee(0, initial, slice[0])
-
-	tmp := make([]T, 2)
-	for i := 1; i < len(slice); i++ {
-		tmp[0] = result
-		tmp[1] = slice[i]
-		result = iteratee(i, tmp[0], tmp[1])
-	}
-
-	return result
+	return accumulator
 }

 // ReduceBy produces a value from slice by accumulating the result of each element as passed through the reducer function.
@@ -625,35 +618,34 @@ func IntSlice(slice any) []int {
 	return result
 }

-// DeleteAt delete the element of slice from start index to end index - 1.
+// DeleteAt delete the element of slice at index.
 // Play: https://go.dev/play/p/pJ-d6MUWcvK
-func DeleteAt[T any](slice []T, start int, end ...int) []T {
-	size := len(slice)
-
-	if start < 0 || start >= size {
-		return slice
+func DeleteAt[T any](slice []T, index int) []T {
+	if index >= len(slice) {
+		index = len(slice) - 1
 	}

-	if len(end) > 0 {
-		end := end[0]
-		if end <= start {
-			return slice
-		}
-		if end > size {
-			end = size
-		}
+	result := make([]T, len(slice)-1)
+	copy(result, slice[:index])
+	copy(result[index:], slice[index+1:])

-		slice = append(slice[:start], slice[end:]...)
-		return slice
+	return result
+}
+
+// DeleteRange delete the element of slice from start index to end index（exclude).
+// Play: todo
+func DeleteRange[T any](slice []T, start, end int) []T {
+	result := make([]T, 0, len(slice)-(end-start))
+
+	for i := 0; i < start; i++ {
+		result = append(result, slice[i])
 	}

-	if start == size-1 {
-		slice = slice[:start]
-	} else {
-		slice = append(slice[:start], slice[start+1:]...)
+	for i := end; i < len(slice); i++ {
+		result = append(result, slice[i])
 	}

-	return slice
+	return result
 }

 // Drop drop n elements from the start of a slice.
--- a/slice/slice_example_test.go
+++ b/slice/slice_example_test.go
@@ -594,18 +594,46 @@ func ExampleIntSlice() {
 }

 func ExampleDeleteAt() {
-	result1 := DeleteAt([]string{"a", "b", "c"}, -1)
-	result2 := DeleteAt([]string{"a", "b", "c"}, 0)
-	result3 := DeleteAt([]string{"a", "b", "c"}, 0, 2)
+	chars := []string{"a", "b", "c", "d", "e"}
+
+	result1 := DeleteAt(chars, 0)
+	result2 := DeleteAt(chars, 4)
+	result3 := DeleteAt(chars, 5)
+	result4 := DeleteAt(chars, 6)

 	fmt.Println(result1)
 	fmt.Println(result2)
 	fmt.Println(result3)
+	fmt.Println(result4)

 	// Output:
-	// [a b c]
-	// [b c]
-	// [c]
+	// [b c d e]
+	// [a b c d]
+	// [a b c d]
+	// [a b c d]
+}
+
+func ExampleDeleteRange() {
+	chars := []string{"a", "b", "c", "d", "e"}
+
+	result1 := DeleteRange(chars, 0, 0)
+	result2 := DeleteRange(chars, 0, 1)
+	result3 := DeleteRange(chars, 0, 3)
+	result4 := DeleteRange(chars, 0, 4)
+	result5 := DeleteRange(chars, 0, 5)
+
+	fmt.Println(result1)
+	fmt.Println(result2)
+	fmt.Println(result3)
+	fmt.Println(result4)
+	fmt.Println(result5)
+
+	// Output:
+	// [a b c d e]
+	// [b c d e]
+	// [d e]
+	// [e]
+	// []
 }

 func ExampleDrop() {
--- a/slice/slice_test.go
+++ b/slice/slice_test.go
@@ -572,19 +572,27 @@ func TestDeleteAt(t *testing.T) {
 	t.Parallel()

 	assert := internal.NewAssert(t, "TestDeleteAt")
+	arr := []int{1, 2, 3, 4, 5}

-	assert.Equal([]string{"a", "b", "c"}, DeleteAt([]string{"a", "b", "c"}, -1))
-	assert.Equal([]string{"a", "b", "c"}, DeleteAt([]string{"a", "b", "c"}, 3))
-	assert.Equal([]string{"b", "c"}, DeleteAt([]string{"a", "b", "c"}, 0))
-	assert.Equal([]string{"a", "c"}, DeleteAt([]string{"a", "b", "c"}, 1))
-	assert.Equal([]string{"a", "b"}, DeleteAt([]string{"a", "b", "c"}, 2))
+	assert.Equal([]int{2, 3, 4, 5}, DeleteAt(arr, 0))
+	assert.Equal([]int{1, 2, 3, 4}, DeleteAt(arr, 4))

-	assert.Equal([]string{"b", "c"}, DeleteAt([]string{"a", "b", "c"}, 0, 1))
-	assert.Equal([]string{"c"}, DeleteAt([]string{"a", "b", "c"}, 0, 2))
-	assert.Equal([]string{}, DeleteAt([]string{"a", "b", "c"}, 0, 3))
-	assert.Equal([]string{}, DeleteAt([]string{"a", "b", "c"}, 0, 4))
-	assert.Equal([]string{"a"}, DeleteAt([]string{"a", "b", "c"}, 1, 3))
-	assert.Equal([]string{"a"}, DeleteAt([]string{"a", "b", "c"}, 1, 4))
+	assert.Equal([]int{1, 2, 3, 4}, DeleteAt(arr, 5))
+	assert.Equal([]int{1, 2, 3, 4}, DeleteAt(arr, 6))
+
+	assert.Equal([]int{1, 2, 3, 4, 5}, arr)
+}
+
+func TestDeleteRange(t *testing.T) {
+	t.Parallel()
+
+	assert := internal.NewAssert(t, "TestDeleteRange")
+
+	arr := []int{1, 2, 3, 4, 5}
+
+	assert.Equal([]int{1, 2, 3, 4, 5}, DeleteRange(arr, 0, 0))
+	assert.Equal([]int{2, 3, 4, 5}, DeleteRange(arr, 0, 1))
+	assert.Equal([]int{4, 5}, DeleteRange(arr, 0, 3))
 }

 func TestDrop(t *testing.T) {
--- a/structs/field.go
+++ b/structs/field.go
@@ -52,6 +52,16 @@ func (f *Field) IsZero() bool {
 	return reflect.DeepEqual(z, v)
 }

+// IsNil returns true if the given field is nil value.
+func (f *Field) IsNil() bool {
+	v := f.Value()
+	if v == nil || (reflect.ValueOf(v)).Kind() == reflect.Ptr && reflect.ValueOf(v).IsNil() {
+		return true
+	}
+
+	return false
+}
+
 // Name returns the name of the given field
 func (f *Field) Name() string {
 	return f.field.Name
@@ -111,7 +121,9 @@ func (f *Field) mapValue(value any) any {
 			ret = v.Interface()
 		}
 	default:
-		ret = v.Interface()
+		if v.Kind().String() != "invalid" {
+			ret = v.Interface()
+		}
 	}
 	return ret
 }
--- a/structs/struct.go
+++ b/structs/struct.go
@@ -2,6 +2,7 @@
 package structs

 import (
+	"fmt"
 	"reflect"

 	"github.com/duke-git/lancet/v2/pointer"
@@ -61,7 +62,7 @@ func New(value any, tagName ...string) *Struct {
 // ToMap convert the exported fields of a struct to map.
 func (s *Struct) ToMap() (map[string]any, error) {
 	if !s.IsStruct() {
-		return nil, errInvalidStruct(s)
+		return nil, fmt.Errorf("invalid struct %v", s)
 	}

 	result := make(map[string]any)
@@ -70,9 +71,15 @@ func (s *Struct) ToMap() (map[string]any, error) {
 		if !f.IsExported() || f.tag.IsEmpty() || f.tag.Name == "-" {
 			continue
 		}
+
 		if f.IsZero() && f.tag.HasOption("omitempty") {
 			continue
 		}
+
+		if f.IsNil() {
+			continue
+		}
+
 		result[f.tag.Name] = f.mapValue(f.Value())
 	}

--- a/structs/struct_internal.go
+++ b/structs/struct_internal.go
@@ -1,7 +0,0 @@
-package structs
-
-import "fmt"
-
-func errInvalidStruct(v any) error {
-	return fmt.Errorf("invalid struct %v", v)
-}
--- a/structs/struct_test.go
+++ b/structs/struct_test.go
@@ -65,6 +65,45 @@ func TestStruct_ToMap(t *testing.T) {
 	})
 }

+func Test_ToMap2(t *testing.T) {
+	t.Parallel()
+	assert := internal.NewAssert(t, "TestStruct_ToMap")
+
+	type M struct {
+		Name string `json:"name"`
+	}
+
+	type S struct {
+		ID int `json:"id"`
+		M  *M  `json:"m"`
+	}
+
+	s1 := &S{
+		ID: 1,
+	}
+	var expect1 = map[string]any{"id": 1}
+	map1, err := ToMap(s1)
+
+	assert.IsNil(err)
+	assert.Equal(expect1, map1)
+
+	s2 := &S{
+		ID: 1,
+		M: &M{
+			Name: "test",
+		},
+	}
+	var expect2 = map[string]any{
+		"id": 1,
+		"m": map[string]any{
+			"name": "test",
+		}}
+	map2, err := ToMap(s2)
+
+	assert.IsNil(err)
+	assert.Equal(expect2, map2)
+}
+
 func TestStruct_Fields(t *testing.T) {
 	t.Parallel()

--- a/strutil/string.go
+++ b/strutil/string.go
@@ -4,7 +4,6 @@
 package strutil

 import (
-	"reflect"
 	"regexp"
 	"strings"
 	"unicode"
@@ -380,10 +379,7 @@ func RemoveNonPrintable(str string) string {
 // StringToBytes converts a string to byte slice without a memory allocation.
 // Play: https://go.dev/play/p/7OyFBrf9AxA
 func StringToBytes(str string) (b []byte) {
-	sh := *(*reflect.StringHeader)(unsafe.Pointer(&str))
-	bh := (*reflect.SliceHeader)(unsafe.Pointer(&b))
-	bh.Data, bh.Len, bh.Cap = sh.Data, sh.Len, sh.Len
-	return b
+	return *(*[]byte)(unsafe.Pointer(&str))
 }

 // BytesToString converts a byte slice to string without a memory allocation.
Author	SHA1	Message	Date
dudaodong	6d4fc981b6	release v2.2.9	2024-02-01 10:03:26 +08:00
dudaodong	4c21fe700c	refactor: update StringToBytes logic	2024-01-30 10:46:55 +08:00
pigwantacat	b7370e8ef8	refactor:refactor random function (#164 ) Co-authored-by: zhuhebin <zhuhebin@fengtaisec.com>	2024-01-30 10:00:14 +08:00
dudaodong	38920e3be6	fix: fix issue #162	2024-01-29 11:00:50 +08:00
dudaodong	a630a7cda9	refactor: remove struct_internal.go	2024-01-29 10:02:36 +08:00
dudaodong	66dfd9c4fd	refactor: refact Comma function	2024-01-25 16:45:17 +08:00
dudaodong	be62aaac9b	refactor: update signature of WriteMapsToCsv function g	2024-01-24 11:54:42 +08:00
dudaodong	e0c9ccbce3	doc: add DeleteRange	2024-01-23 17:27:28 +08:00
dudaodong	d2d1e5a055	feat: refact DeleteAt and add DeleteRange function	2024-01-22 15:34:35 +08:00
dudaodong	bbc58c7e46	fix: fix the map key order issue of WriteMapsToCsv	2024-01-22 11:10:02 +08:00
dudaodong	ac2ecceaec	refactor: refact reduce function	2024-01-03 10:46:28 +08:00
dudaodong	a06bb8ee6a	fix: fix unit test for WriteMapsToCsv	2024-01-01 18:32:41 +08:00
dudaodong	27b5702fd3	fix: fix unit test for WriteMapsToCsv	2024-01-01 17:51:32 +08:00
dudaodong	b2c3fa0ab8	fix: fix golint issue	2024-01-01 17:43:11 +08:00
dudaodong	4afc838937	doc: add doc for WriteMapsToCsv	2024-01-01 17:40:32 +08:00
colorcrow	3482f80d1c	WriteCsvFile自定义分割符,增加map切片写入csv，增加追踪函数运行时间的函数 (#157 ) * WriteCsvFile now support custom delimiter,Add write map slice to csv * add trace func time	2024-01-01 16:54:04 +08:00
suacrbah	565f2893b9	feat: add support for seeking and read one line at a time from file (#158 ) * feat: add support for seeking and read one line at a time from file * feat: add support for calculating folder total size --------- Co-authored-by: Suacrbah <5744580+Suacrbah@user.noreply.gitee.com>	2024-01-01 16:50:54 +08:00