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/*
This source file is part of the Swift.org open source project
Copyright (c) 2021 Apple Inc. and the Swift project authors
Licensed under Apache License v2.0 with Runtime Library Exception
See https://swift.org/LICENSE.txt for license information
See https://swift.org/CONTRIBUTORS.txt for Swift project authors
*/
import Foundation
extension RangeReplaceableCollection {
/// Groups successive elements as long as check determines that they belong together.
///
/// - Parameter belongsInGroupWithPrevious: A check whether the given element belongs in the same group as the previous element
/// - Returns: An array of subsequences of elements that belong together.
func group(asLongAs belongsInGroupWithPrevious: (_ previous: Element, _ current: Element) throws -> Bool) rethrows -> [SubSequence] {
var result = [SubSequence]()
let indexPairs = zip(indices, indices.dropFirst())
var splitStart = startIndex
for (previous, current) in indexPairs where try !belongsInGroupWithPrevious(self[previous], self[current]) {
result.append(self[splitStart...previous])
splitStart = current
}
result.append(self[splitStart...])
return result
}
}
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