docs: add formArray clear() example clarifies array manipulation

Author: SkyZeroZx

adev/src/content/guide/forms/overview.md

@@ -73,7 +73,7 @@ The `[formControl]` directive links the explicitly created `FormControl` instanc
 The following component implements an input field for a single control, using reactive forms.
 In this example, the form model is the `FormControl` instance.
 
-<docs-code path="adev/src/content/examples/forms-overview/src/app/reactive/favorite-color/favorite-color.component.ts"/>
+<docs-code language="angular-ts" path="adev/src/content/examples/forms-overview/src/app/reactive/favorite-color/favorite-color.component.ts"/>
 
 IMPORTANT: In reactive forms, the form model is the source of truth; it provides the value and status of the form element at any given point in time, through the `[formControl]` directive on the `<input>` element.
 
@@ -84,7 +84,7 @@ The directive `NgModel` creates and manages a `FormControl` instance for a given
 
 The following component implements the same input field for a single control, using template-driven forms.
 
-<docs-code path="adev/src/content/examples/forms-overview/src/app/template/favorite-color/favorite-color.component.ts"/>
+<docs-code language="angular-ts" path="adev/src/content/examples/forms-overview/src/app/template/favorite-color/favorite-color.component.ts"/>
 
 IMPORTANT: In a template-driven form the source of truth is the template. The `NgModel` directive automatically manages the `FormControl` instance for you.
 

adev/src/content/guide/forms/typed-forms.md

@@ -110,6 +110,14 @@ This `FormArray` will have the inner controls type `FormControl<string|null>`.
 
 If you want to have multiple different element types inside the array, you must use `UntypedFormArray`, because TypeScript cannot infer which element type will occur at which position.
 
+A `FormArray` also provides a `clear()` method to remove all controls it contains:
+
+```ts
+const aliases = new FormArray([new FormControl('ngDev'), new FormControl('ngAwesome')]);
+aliases.clear();
+console.log(aliases.length); // 0
+```
+
 ## `FormGroup` and `FormRecord`
 
 Angular provides the `FormGroup` type for forms with an enumerated set of keys, and a type called `FormRecord`, for open-ended or dynamic groups.