Merge pull request #300104 from mumian/0520-bcp076

Document bcp076

Author: Stacyrch140

articles/azure-resource-manager/bicep/bicep-core-diagnostics.md

@@ -3,7 +3,7 @@ title: Bicep warnings and error codes
 description: Understand Bicep warnings and error codes.
 ms.topic: conceptual
 ms.custom: devx-track-azurecli, devx-track-bicep, devx-track-arm-template
-ms.date: 03/25/2025
+ms.date: 05/20/2025
 ---
 
 # Bicep core diagnostics
@@ -81,7 +81,7 @@ If you need more information about a particular diagnostic code, select the **Fe
 | <a id='BCP073' />[BCP073](./diagnostics/bcp073.md) | Error/Warning | The property \<property-name> is read-only. Expressions can't be assigned to read-only properties. |
 | <a id='BCP074' />BCP074 | Error | Indexing over arrays requires an index of type "{LanguageConstants.Int}", but the provided index was of type "{wrongType}". |
 | <a id='BCP075' />BCP075 | Error | Indexing over objects requires an index of type "{LanguageConstants.String}", but the provided index was of type "{wrongType}". |
-| <a id='BCP076' />BCP076 | Error | Can't index over expression of type "{wrongType}". Arrays or objects are required. |
+| <a id='BCP076' />[BCP076](./diagnostics/bcp076.md) | Error | Can't index over expression of type \<wrong-type>. Arrays or objects are required. |
 | <a id='BCP077' />[BCP077](./diagnostics/bcp077.md) | Error/Warning | The property \<property-name> on type \<type-name> is write-only. Write-only properties can't be accessed. |
 | <a id='BCP078' />[BCP078](./diagnostics/bcp078.md) | Error/Warning | The property \<property-name> requires a value of type \<type-name>, but none was supplied. |
 | <a id='BCP079' />BCP079 | Error | This expression is referencing its own declaration, which isn't allowed. |

articles/azure-resource-manager/bicep/diagnostics/bcp076.md

@@ -0,0 +1,58 @@
+---
+title: BCP076
+description: Can't index over expression of type <wrong-type>. Arrays or objects are required.
+ms.topic: reference
+ms.custom: devx-track-bicep
+ms.date: 05/20/2025
+---
+
+# Bicep diagnostic code - BCP076
+
+This diagnostic occurs when attempting to use the index operator ([] or [^index]) on an expression that isn't an array or object. This happens when the expression being indexed is of an incompatible type, such as a string, integer, boolean, or null.
+
+## Description
+
+Can't index over expression of type \<wrong-type>. Arrays or objects are required.
+
+## Level
+
+Error
+
+## Examples
+
+The following code attempts to index a string, which triggers BCP076:
+
+```bicep
+var notAnArray = 'hello'
+var invalidAccess = notAnArray[0] // Error: BCP076 - Can't index over expression of type 'hello'. Arrays or objects are required.
+```
+
+This code tries to use the reverse index operator on an integer:
+
+```bicep
+var number = 42
+var invalidIndex = number[^1] // Error: BCP076 - Can't index over expression of type '42'. Arrays or objects are required.
+```
+
+To fix the error, ensure the expression is an array or object:
+
+```bicep
+var sizes = ['small', 'medium', 'large']
+var first = sizes[0] // Returns 'small'
+var last = sizes[^1] // Returns 'large'
+
+var settings = { key1: 'value1', key2: 'value2' }
+var value = settings['key1'] // Returns 'value1'
+```
+
+If you need to extract parts of a string, use string functions like [split](../bicep-functions-string.md#split) or [substring](../bicep-functions-string.md#substring):
+
+```bicep
+var text = 'hello'
+var chars = split(text, '') // Returns ['h', 'e', 'l', 'l', 'o']
+var firstChar = chars[0] // Returns 'h'
+```
+
+## Next steps
+
+For more information about Bicep diagnostics, see [Bicep core diagnostics](../bicep-core-diagnostics.md).

articles/azure-resource-manager/bicep/toc.yml

@@ -663,6 +663,8 @@ items:
       href: diagnostics/bcp072.md
     - name: BCP073
       href: diagnostics/bcp073.md
+    - name: BCP076
+      href: diagnostics/bcp076.md
     - name: BCP077
       href: diagnostics/bcp077.md
     - name: BCP078