Merge pull request #248038 from mumian/0809-symbolic

Use symbolic name and languageVersion 2.0

Author: JamesJBarnett

articles/azure-resource-manager/templates/copy-resources.md

@@ -3,7 +3,7 @@ title: Deploy multiple instances of resources
 description: Use copy operation and arrays in an Azure Resource Manager template (ARM template) to deploy resource type many times.
 ms.topic: conceptual
 ms.custom: devx-track-arm-template
-ms.date: 05/22/2023
+ms.date: 08/30/2023
 ---
 
 # Resource iteration in ARM templates
@@ -91,7 +91,7 @@ The following example creates the number of storage accounts specified in the `s
 Notice that the name of each resource includes the `copyIndex()` function, which returns the current iteration in the loop. `copyIndex()` is zero-based. So, the following example:
 
 ```json
-"name": "[concat('storage', copyIndex())]",
+"name": "[format('storage{0}', copyIndex())]",
 ```
 
 Creates these names:
@@ -103,7 +103,7 @@ Creates these names:
 To offset the index value, you can pass a value in the `copyIndex()` function. The number of iterations is still specified in the copy element, but the value of `copyIndex` is offset by the specified value. So, the following example:
 
 ```json
-"name": "[concat('storage', copyIndex(1))]",
+"name": "[format('storage{0}', copyIndex(1))]",
 ```
 
 Creates these names:
@@ -156,6 +156,64 @@ The following example creates one storage account for each name provided in the
 
 If you want to return values from the deployed resources, you can use [copy in the outputs section](copy-outputs.md).
 
+### Use symbolic name
+
+[Symbolic name](./resource-declaration.md#use-symbolic-name) will be assigned to resource copy loops. The loop index is zero-based. In the following example, `myStorages[1]` references the second resource in the resource loop.
+
+```json
+{
+  "$schema": "https://schema.management.azure.com/schemas/2019-04-01/deploymentTemplate.json#",
+  "languageVersion": "2.0",
+  "contentVersion": "1.0.0.0",
+  "parameters": {
+    "location": {
+      "type": "string",
+      "defaultValue": "[resourceGroup().location]"
+    },
+    "storageCount": {
+      "type": "int",
+      "defaultValue": 2
+    }
+  },
+  "resources": {
+    "myStorages": {
+      "type": "Microsoft.Storage/storageAccounts",
+      "apiVersion": "2022-09-01",
+      "name": "[format('{0}storage{1}', copyIndex(), uniqueString(resourceGroup().id))]",
+      "location": "[parameters('location')]",
+      "sku": {
+        "name": "Standard_LRS"
+      },
+      "kind": "Storage",
+      "properties": {},
+      "copy": {
+        "name": "storagecopy",
+        "count": "[parameters('storageCount')]"
+      }
+    }
+  },
+  "outputs": {
+    "storageEndpoint":{
+      "type": "object",
+      "value": "[reference('myStorages[1]').primaryEndpoints]"
+    }
+  }
+}
+```
+
+If the index is a runtime value, format the reference yourself.  For example
+
+```json
+"outputs": {
+  "storageEndpoint":{
+    "type": "object",
+    "value": "[reference(format('myStorages[{0}]', variables('runtimeIndex'))).primaryEndpoints]"
+  }
+}
+```
+
+Symbolic names can be used in [dependsOn arrays](./resource-dependency.md#depend-on-resources-in-a-loop). If a symbolic name is for a copy loop, all resources in the loop are added as dependencies. For more information, see [Depends on resources in a loop](./resource-dependency.md#depend-on-resources-in-a-loop).
+
 ## Serial or Parallel
 
 By default, Resource Manager creates the resources in parallel. It applies no limit to the number of resources deployed in parallel, other than the total limit of 800 resources in the template. The order in which they're created isn't guaranteed.
@@ -244,7 +302,7 @@ The following example shows the implementation.
 },
 {
   "type": "Microsoft.DataFactory/factories/datasets",
-  "name": "[concat('exampleDataFactory', '/', 'exampleDataSet', copyIndex())]",
+  "name": "[format('exampleDataFactory/exampleDataSet{0}', copyIndex())]",
   "dependsOn": [
     "exampleDataFactory"
   ],