---
schema_version: "1"
id: a127f2375496d647257a68fbb56bee8a50a52a80e5f0e891c147fb603199e0d0
title: Imperative Extensions
collection: developer
version: current
locale: en-us
portal_url: https://docs.salesforce.com/developer/current/en-us/lwc/utam/references/imperative-extensions.md
canonical_url: https://developer.salesforce.com/docs/platform/utam/references/utam-grammar/imperative-extensions.html
source_site: developer.salesforce.com
content_type: documentation
content_hash: 4ef96dae972be3bcba6c19352e1fbb1eff0eab50d34b81e2dfa3dc5ceb6a8d25
products:
  - UI Test Automation Model
  - lwc
---
# Imperative Extensions

Imperative extensions enable you to create reusable utility code to address complex use cases that aren't supported in UTAM's JSON grammar. For example, you can't use the JSON grammar to navigate a data table where each column shows data from a different type of component with different markup.

**important:** While imperative extensions are powerful, only use them as a last resort. They violate the declarative nature of UTAM and require you to individually implement and maintain them in each programming language that you use with UTAM.

Declare imperative utility code in a `compose` statement. A page object can reference multiple utilities.

```json
{
  "methods": [
    {
      "name": "myMethod",
      "compose": [
        {
          "applyExternal": {
            "type": "utam-lst/utils/lst/relatedListContainerUtils",
            "invoke": "cardUtility1",
            "args": [
              {
                "name": "stringArg",
                "type": "string"
              }
            ]
          }
        },
        {
          "applyExternal": {
            "type": "utam-lst/utils/lst/relatedListContainerUtils",
            "invoke": "cardUtility2",
            "args": [
              {
                "name": "booleanArg",
                "type": "boolean"
              }
            ]
          }
        }
      ]
    }
  ]
}
```

An imperative extension in a `compose` statement has these properties:

- `element` (Optional.) String. A reference to the element passed as the first parameter to the utility code. The default value is `self` so if no element is set, we pass the page object itself. You can omit this property because you can access the elements from the page object reference passed to the utility code.
- `applyExternal` (Required) Object. Declares an imperative extension and has these properties:
  - `type` (Required) String. A reference to the executable code to import: either a Java class or a JavaScript ES module.
  - `invoke` (Required) String. A reference to the method name to call: a named function in JavaScript or a static method in Java.
  - `args` (Optional) Array. If the code needs parameters, provide them in an array. Each element of the array has these properties:
    - `name` (Required) String. A parameter name that is unique in the scope of the `args` array.
    - `type` (Required) String. A parameter type, which is a primitive type, locator or a function.

For examples of Java and JavaScript code implementations, see [Guide: Imperative Extensions](/guide/imperative).