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--- title: Bicep accessor operators description: Describes Bicep resource access operator and property access operator. ms.topic: reference ms.custom: devx-track-bicep ms.date: 12/22/2025 --- # Bicep accessor operators The accessor operators are used to access child resources, properties on objects, and elements in an array. You can also use the property accessor to use some functions. | Operator | Name | | ---- | ---- | | `[]` | [Index accessor](#index-accessor) | | `[^index]` | [Reverse index accessor](#reverse-index-accessor) | | `.` | [Function accessor](#function-accessor) | | `::` | [Nested resource accessor](#nested-resource-accessor) | | `.` | [Property accessor](#property-accessor) | ## Index accessor `array[integerIndex]` `object['stringIndex']` Use the index accessor to get either an element from an array or a property from an object. For an **array**, provide the index as an **integer**. The integer matches the zero-based position of the element to retrieve. For an **object**, provide the index as a **string**. The string matches the name of the object to retrieve. The following example gets an element in an array. ```bicep var arrayVar = [ 'Coho' 'Contoso' 'Fabrikam' ] output accessorResult string = arrayVar[1] ``` Output from the example: | Name | Type | Value | | ---- | ---- | ---- | | accessorResult | string | 'Contoso' | The next example gets a property on an object. ```bicep var environmentSettings = { dev: { name: 'Development' } prod: { name: 'Production' } } output accessorResult string = environmentSettings['dev'].name ``` Output from the example: | Name | Type | Value | | ---- | ---- | ---- | | accessorResult | string | 'Development' | ## Reverse index accessor Beginning with [Bicep CLI version 0.34.x](https://github.com/Azure/bicep/releases/tag/v0.34.1), the reverse index accessor operator (`^`) allows you to retrieve an element from an array by counting from the end. This one-based index means `^1` returns the last item, `^2` the second-to-last, and so on. The index must be a positive integer greater than zero and can be specified as a literal or an expression that evaluates to an integer. `array[^index]` If the index exceeds the length of the array, a compilation error occurs for static indices, or a runtime error occurs for dynamic indices. For constant arrays, the operator is evaluated at compile time. For dynamic inputs, such as [parameters](./parameters.md), evaluation occurs at deployment time. ### Example ```bicep var items = [ 'apple' 'banana' 'orange' 'grape' ] output secondToLast string = items[^2] ``` Output from the example: | Name | Type | Value | | ---- | ---- | ---- | | secondToLast | string | 'orange' | ## Function accessor `resourceName.functionName()` Two functions - [getSecret](bicep-functions-resource.md#getsecret) and [list*](bicep-functions-resource.md#list) - support the accessor operator for calling the function. These two functions are the only functions that support the accessor operator. ### Example The following example references an existing key vault, then uses `getSecret` to pass a secret to a module. ```bicep resource kv 'Microsoft.KeyVault/vaults@2025-05-01' existing = { name: kvName scope: resourceGroup(subscriptionId, kvResourceGroup ) } module sql './sql.bicep' = { name: 'deploySQL' params: { sqlServerName: sqlServerName adminLogin: adminLogin adminPassword: kv.getSecret('vmAdminPassword') } } ``` ## Nested resource accessor `parentResource::nestedResource` A nested resource is a resource that is declared within another resource. Use the nested resource accessor `::` to access that nested resources from outside of the parent resource. Within the parent resource, you reference the nested resource with just the symbolic name. You only need to use the nested resource accessor when referencing the nested resource from outside of the parent resource. ### Example The following example shows how to reference a nested resource from within the parent resource and from outside of the parent resource. ```bicep resource demoParent 'demo.Rp/parentType@2024-01-01' = { name: 'demoParent' location: 'West US' // Declare a nested resource within 'demoParent' resource demoNested 'childType' = { name: 'demoNested' properties: { displayName: 'The nested instance.' } } // Declare another nested resource resource demoSibling 'childType' = { name: 'demoSibling' properties: { // Use symbolic name to reference because this line is within demoParent displayName: 'Sibling of ${demoNested.properties.displayName}' } } } // Use nested accessor to reference because this line is outside of demoParent output displayName string = demoParent::demoNested.properties.displayName ``` ## Property accessor `objectName.propertyName` Use property accessors to access properties of an object. Property accessors can be used with any object, including parameters and variables that are objects. You get an error when you use the property access on an expression that isn't an object. ### Example The following example shows an object variable and how to access the properties. ```bicep var x = { y: { z: 'Hello' a: true } q: 42 } output outputZ string = x.y.z output outputQ int = x.q ``` Output from the example: | Name | Type | Value | | ---- | ---- | ---- | | `outputZ` | string | 'Hello' | | `outputQ` | integer | 42 | Typically, you use the property accessor with a resource deployed in the Bicep file. The following example creates a public IP address and uses property accessors to return a value from the deployed resource. ```bicep resource publicIp 'Microsoft.Network/publicIPAddresses@2025-01-01' = { name: publicIpResourceName location: location properties: { publicIPAllocationMethod: dynamicAllocation ? 'Dynamic' : 'Static' dnsSettings: { domainNameLabel: publicIpDnsLabel } } } // Use property accessor to get value output ipFqdn string = publicIp.properties.dnsSettings.fqdn ``` ## Next steps - To run the examples, use Azure CLI or Azure PowerShell to [deploy a Bicep file](./quickstart-create-bicep-use-visual-studio-code.md#deploy-the-bicep-file). - To create a Bicep file, see [Quickstart: Create Bicep files with Visual Studio Code](./quickstart-create-bicep-use-visual-studio-code.md). - For information about how to resolve Bicep type errors, see [Any function for Bicep](./bicep-functions-any.md).