> 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 %}


---

# Agent Instructions
This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com.

## Querying This Documentation
If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter, and the optional `goal` query parameter:

```
GET https://gauntletlang.gitbook.io/docs/scope-variables.md?ask=<question>&goal=<endgoal>
```

`ask` is the immediate question: it should be specific, self-contained, and written in natural language.
`goal` is optional and describes the broader end goal you are ultimately trying to accomplish on behalf of the user. GitBook uses it to tailor the answer towards what is most useful for that goal.

The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.