NBKDoubleWidth+Words+Pointers.swift

//=----------------------------------------------------------------------------=
// This source file is part of the Numberick open source project.
//
// Copyright (c) 2023 Oscar Byström Ericsson
// Licensed under Apache License, Version 2.0
//
// See http://www.apache.org/licenses/LICENSE-2.0 for license information.
//=----------------------------------------------------------------------------=

import NBKCoreKit

//*============================================================================*
// MARK: * NBK x Double Width x Words x Pointers
//*============================================================================*

extension NBKDoubleWidth {
    
    //=------------------------------------------------------------------------=
    // MARK: Details x Contiguous UInt Collection
    //=------------------------------------------------------------------------=
    
    /// Grants unsafe access to the collection's contiguous storage.
    ///
    /// The elements of the contiguous storage appear in the order of the collection.
    ///
    @inlinable public func withContiguousStorage<T>(
    _ body: (UnsafeBufferPointer<UInt>) throws -> T) rethrows -> T {
        var base = self; return try base.withUnsafeMutableData(as: UInt.self) { data in
            #if _endian(big)
            data.reverse()
            #endif
            return try body(UnsafeBufferPointer(data))
        }
    }
    
    /// Grants unsafe access to the collection's contiguous storage.
    ///
    /// The elements of the contiguous storage appear in the order of the collection.
    ///
    /// - Note: This member is required by `Swift.Sequence`.
    ///
    @inlinable public func withContiguousStorageIfAvailable<T>(
    _ body: (UnsafeBufferPointer<UInt>) throws -> T) rethrows -> T? {
        try self.withContiguousStorage(body)
    }
    
    /// Grants unsafe access to the collection's contiguous mutable storage.
    ///
    /// The elements of the contiguous mutable storage appear in the order of the collection.
    ///
    @inlinable public mutating func withContiguousMutableStorage<T>(
    _ body: (inout UnsafeMutableBufferPointer<UInt>) throws -> T) rethrows -> T {
        return try self.withUnsafeMutableData(as: UInt.self) { data in
            #if _endian(big)
            do    { data.reverse() }
            defer { data.reverse() }
            #endif
            return try body(&data)
        }
    }
    
    /// Grants unsafe access to the collection's contiguous mutable storage.
    ///
    /// The elements of the contiguous mutable storage appear in the order of the collection.
    ///
    /// - Note: This member is required by `Swift.MutableCollection`.
    ///
    @inlinable public mutating func withContiguousMutableStorageIfAvailable<T>(
    _ body: (inout UnsafeMutableBufferPointer<UInt>) throws -> T) rethrows -> T? {
        try  self.withContiguousMutableStorage(body)
    }
}