> For the complete documentation index, see [llms.txt](https://ineelhere.gitbook.io/code-with-go/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://ineelhere.gitbook.io/code-with-go/7-switch.md).

# Switch

The provided Go code demonstrates the usage of the `switch` statement in various scenarios.

Let's break down the code step by step:

```go
package main

import (
    "fmt"
    "time"
)

func main() {
    // Example 1: Basic switch statement with an integer
    i := 2
    fmt.Print("Write ", i, " as ")
    switch i {
    case 1:
        fmt.Println("one")
    case 2:
        fmt.Println("two")
    case 3:
        fmt.Println("three")
    }

    // Example 2: Switch statement with time.Weekday
    switch time.Now().Weekday() {
    case time.Saturday, time.Sunday:
        fmt.Println("It's the weekend")
    default:
        fmt.Println("It's a weekday")
    }

    // Example 3: Switch statement without an expression
    // Evaluates the current time and checks if it's before or after noon
    t := time.Now()
    switch {
    case t.Hour() < 12:
        fmt.Println("It's before noon")
    default:
        fmt.Println("It's after noon")
    }

    // Example 4: Switch statement with a type assertion
    // Uses a function literal (anonymous function) to determine the type of the input
    whatAmI := func(i interface{}) {
        switch t := i.(type) {
        case bool:
            fmt.Println("I'm a bool")
        case int:
            fmt.Println("I'm an int")
        default:
            fmt.Printf("Don't know type %T\n", t)
        }
    }
    whatAmI(true)
    whatAmI(1)
    whatAmI("hey")
}
```

Explanation:

1. **Basic Switch with Integer (`i`):**
   * The code initializes an integer `i` with the value 2.
   * The `switch` statement checks the value of `i` and prints the corresponding word for the number.
2. **Switch with `time.Weekday`:**
   * The code uses the `time.Now().Weekday()` function to get the current day of the week.
   * The `switch` statement checks if it's Saturday or Sunday and prints a message accordingly.
3. **Switch without Expression (`t.Hour()`):**
   * The code uses the current time (`time.Now()`) and checks the hour using `t.Hour()`.
   * The `switch` statement doesn't have a specific expression but evaluates conditions based on the hour.
4. **Switch with Type Assertion (`whatAmI` function):**

   * The code defines a function `whatAmI` that takes an empty interface (`interface{}`), allowing it to accept values of any type.
   * Inside the function, a `switch` statement uses type assertion (`i.(type)`) to determine the type of the input and prints a message accordingly.

   Example outputs:

   * `I'm a bool` for `true`
   * `I'm an int` for `1`
   * `Don't know type string` for `"hey"`

This code showcases the flexibility and power of the `switch` statement in Go, allowing developers to handle different types of conditions and expressions efficiently.

### Output

```
Write 2 as two
It's a weekday
It's before noon
I'm a bool
I'm an int
Don't know type string
```