Function isEnglish

isEnglish(locales?: unknown): boolean
Checks whether all resolved locales in the input belong to the English language family ('en-*').
Parameters
- Optionallocales: unknown
  Single or multiple locale identifiers
Returns boolean
True if at least one valid locale exists and all resolved locales are English
Example
```
isEnglish('en-US'); // true
isEnglish(['en-US', 'en-GB']); // true
isEnglish(['en-US', 'fr-FR']); // false
```
- Defined in packages/library/src/common/runtime/international.library.ts:400