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# CFLocaleCreateCanonicalLocaleIdentifierFromString(_:_:)

Returns a canonical locale identifier by mapping an arbitrary locale identification string to the canonical identifier.

```
func CFLocaleCreateCanonicalLocaleIdentifierFromString(_ allocator: CFAllocator!, _ localeIdentifier: CFString!) -> CFLocaleIdentifier!
```

## Parameters

`allocator`

The allocator to use to allocate memory for the new object. Pass `NULL` or kCFAllocatorDefault to use the current default allocator.

`localeIdentifier`

A string representation of an arbitrary locale identifier (for example, “English”).

## Return Value

A canonical locale identifier created by mapping the arbitrary locale identification string to the canonical identifier for the corresponding locale (for example, “en”). Returns `NULL` if there was a problem creating the object. Ownership follows the [The Create Rule](https://developer.apple.com/library/archive/documentation/CoreFoundation/Conceptual/CFMemoryMgmt/Concepts/Ownership.html#//apple_ref/doc/uid/20001148-103029).

## Discussion

---

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