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# isLenient

A Boolean value that indicates whether the receiver uses heuristics when parsing a string.

```
var isLenient: Bool { get set }
```

## Discussion

<doc://com.apple.documentation/documentation/Swift/true> if the receiver has been set to use heuristics when parsing a string to guess at the date which is intended, otherwise <doc://com.apple.documentation/documentation/Swift/false>.

If a formatter is set to be lenient, when parsing a string it uses heuristics to guess at the date which is intended. As with any guessing, it may get the result date wrong (that is, a date other than that which was intended).

---

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