# RangeExpression Implementations ## Topics ### Operators [`static func ~= (Self, Self.Bound) -> Bool`](/documentation/Swift/PartialRangeUpTo/~=(_:_:)) Returns a Boolean value indicating whether a value is included in a range. ### Instance Methods [`func contains(Bound) -> Bool`](/documentation/Swift/PartialRangeUpTo/contains(_:)) Returns a Boolean value indicating whether the given element is contained within the range expression. [`func relative(to: C) -> Range`](/documentation/Swift/PartialRangeUpTo/relative(to:)) Returns the range of indices described by this range expression within the given collection. --- Copyright © 2026 Apple Inc. All rights reserved. | [Terms of Use](https://www.apple.com/legal/internet-services/terms/site.html) | [Privacy Policy](https://www.apple.com/privacy/privacy-policy)