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docs/api/packages/pointer.md

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+# Pointer
+
+pointer 包支持一些指针类型的操作。
+
+<div STYLE="page-break-after: always;"></div>
+
+## 源码:
+
+-   [https://github.com/duke-git/lancet/blob/main/pointer/pointer.go](https://github.com/duke-git/lancet/blob/main/pointer/pointer.go)
+
+<div STYLE="page-break-after: always;"></div>
+
+## 用法:
+
+```go
+import (
+    "github.com/duke-git/lancet/v2/pointer"
+)
+```
+
+<div STYLE="page-break-after: always;"></div>
+
+## 目录
+
+-   [Of](#Of)
+-   [Unwrap](#Unwrap)
+-   [ExtractPointer](#ExtractPointer)
+-   [UnwarpOr](#UnwarpOr)
+-   [UnwarpOrDefault](#UnwarpOrDefault)
+
+<div STYLE="page-break-after: always;"></div>
+
+<link rel="stylesheet" type="text/css" href="../../styles/api_doc.css">
+
+## 文档
+
+### <span id="Of">Of</span>
+
+<p>返回传入参数的指针值。</p>
+
+<b>函数签名:</b>
+
+```go
+func Of[T any](v T) *T
+```
+
+<b>示例:<span class="run-container">[运行](https://go.dev/play/p/HFd70x4DrMj)</span></b>
+
+```go
+package main
+
+import (
+    "fmt"
+    "github.com/duke-git/lancet/v2/pointer"
+)
+
+func main() {
+    result1 := pointer.Of(123)
+    result2 := pointer.Of("abc")
+
+    fmt.Println(*result1)
+    fmt.Println(*result2)
+
+    // Output:
+    // 123
+    // abc
+}
+```
+
+### <span id="Unwrap">Unwrap</span>
+
+<p>返回传入指针指向的值。</p>
+
+<b>函数签名:</b>
+
+```go
+func Unwrap[T any](p *T) T
+```
+
+<b>示例:<span class="run-container">[运行](https://go.dev/play/p/cgeu3g7cjWb)</span></b>
+
+```go
+package main
+
+import (
+    "fmt"
+    "github.com/duke-git/lancet/v2/pointer"
+)
+
+func main() {
+    a := 123
+    b := "abc"
+
+    result1 := pointer.Unwrap(&a)
+    result2 := pointer.Unwrap(&b)
+
+    fmt.Println(result1)
+    fmt.Println(result2)
+
+    // Output:
+    // 123
+    // abc
+}
+```
+
+### <span id="ExtractPointer">ExtractPointer</span>
+
+<p>返回传入interface的底层值。</p>
+
+<b>函数签名:</b>
+
+```go
+func ExtractPointer(value any) any
+```
+
+<b>示例:<span class="run-container">[运行](https://go.dev/play/p/D7HFjeWU2ZP)</span></b>
+
+```go
+package main
+
+import (
+    "fmt"
+    "github.com/duke-git/lancet/v2/pointer"
+)
+
+func main() {
+    a := 1
+    b := &a
+    c := &b
+    d := &c
+
+    result := pointer.ExtractPointer(d)
+
+    fmt.Println(result)
+
+    // Output:
+    // 1
+}
+```
+
+### <span id="UnwarpOr">UnwarpOr</span>
+
+<p>返回指针的值，如果指针为零值，则返回fallback。</p>
+
+<b>函数签名:</b>
+
+```go
+UnwarpOr[T any](p *T, fallback T) T
+```
+
+<b>示例:<span class="run-container">[运行](https://go.dev/play/p/mmNaLC38W8C)</span></b>
+
+```go
+package main
+
+import (
+    "fmt"
+    "github.com/duke-git/lancet/v2/pointer"
+)
+
+func main() {
+	a := 123
+	b := "abc"
+
+	var c *int
+	var d *string
+
+	result1 := pointer.UnwarpOr(&a, 456)
+	result2 := pointer.UnwarpOr(&b, "abc")
+	result3 := pointer.UnwarpOr(c, 456)
+	result4 := pointer.UnwarpOr(d, "def")
+
+	fmt.Println(result1)
+	fmt.Println(result2)
+	fmt.Println(result3)
+	fmt.Println(result4)
+
+	// Output:
+	// 123
+	// abc
+	// 456
+	// def
+}
+```
+
+### <span id="UnwarpOrDefault">UnwarpOrDefault</span>
+
+<p>返回指针的值，如果指针为零值，则返回相应零值。</p>
+
+<b>函数签名:</b>
+
+```go
+UnwarpOrDefault[T any](p *T) T
+```
+
+<b>示例:<span class="run-container">[运行](https://go.dev/play/p/ZnGIHf8_o4E)</span></b>
+
+```go
+package main
+
+import (
+    "fmt"
+    "github.com/duke-git/lancet/v2/pointer"
+)
+
+func main() {
+	a := 123
+	b := "abc"
+
+	var c *int
+	var d *string
+
+	result1 := pointer.UnwarpOrDefault(&a)
+	result2 := pointer.UnwarpOrDefault(&b)
+	result3 := pointer.UnwarpOrDefault(c)
+	result4 := pointer.UnwarpOrDefault(d)
+
+	fmt.Println(result1)
+	fmt.Println(result2)
+	fmt.Println(result3)
+	fmt.Println(result4)
+
+	// Output:
+	// 123
+	// abc
+	// 0
+	//
+}
+```