> For the complete documentation index, see [llms.txt](https://gauntletlang.gitbook.io/docs/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://gauntletlang.gitbook.io/docs/scope-variables.md).

# Scope Variables

## There are two types of scope variable bindings in Gauntlet:

{% hint style="info" %}
Both types of variables are mutable
{% endhint %}

{% hint style="info" %}
For syntax of `varPattern` see [Read before Proceeding](/docs/read-before-proceeding.md#common-placeholders-throughout-documentation)
{% endhint %}

### 1. let-variables

 let-variables use the `:=` operator under the hood. It's syntax is:

```fsharp
let <varPattern> [: TypeName] = <expression>
```

### 2. zero-variables

Zero-variables create an instance of a type's "zero" value. In Gauntlet, the syntax is:

```fsharp
zero <varPattern>: <TypeName>
```

## Working Example

{% tabs %}
{% tab title="Gauntlet" %}

```fsharp
package main

import "fmt" as fmt

fun main(): Unit {
  let a, b, c: Int = (1, 2, 3)
  let myName = "Bobby"
  fmt.println(myName)

  zero myZeroVar: Int
  fmt.println("The number below should be 0, since it's Int's 'zero' value:")
  fmt.println(myZeroVar)
}
```

{% endtab %}

{% tab title="Transpiled" %}

```go
package main

import fmt "fmt"

func main() {
	var a, b, c int = 1, 2, 3
	myName := "Bobby"
	fmt.Println(myName)
	var myZeroVar int
	fmt.Println("The number below should be 0, since it's Int's 'zero' value:")
	fmt.Println(myZeroVar)
	// Eliminates any 'unused variable' errors
	_, _, _, _, _ = a, b, c, myName, myZeroVar

}

```

{% endtab %}

{% tab title="Output" %}

```
Bobby
The number below should be 0, since it's Int's 'zero' value:
0
```

{% endtab %}
{% endtabs %}


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