# initializeMemory(as:from:count:) Initializes the memory referenced by this pointer with the values starting at the given pointer, binds the memory to the values’ type, and returns a typed pointer to the initialized memory. ``` @discardableResult func initializeMemory(as type: T.Type, from source: UnsafePointer, count: Int) -> UnsafeMutablePointer ``` ## Parameters `type` The type to bind this memory to. `source` A pointer to the values to copy. The memory in the region `source..<(source + count)` must be initialized to type `T` and must not overlap the destination region. `count` The number of copies of `value` to copy into memory. `count` must not be negative. ## Return Value A typed pointer to the memory referenced by this raw pointer. ## Discussion The memory referenced by this pointer must be uninitialized or initialized to a trivial type, and must be properly aligned for accessing `T`. The following example allocates enough raw memory to hold four instances of `Int8`, and then uses the `initializeMemory(as:from:count:)` method to initialize the allocated memory. ``` let count = 4 let bytesPointer = UnsafeMutableRawPointer.allocate( byteCount: count * MemoryLayout.stride, alignment: MemoryLayout.alignment) let values: [Int8] = [1, 2, 3, 4] let int8Pointer = values.withUnsafeBufferPointer { buffer in return bytesPointer.initializeMemory(as: Int8.self, from: buffer.baseAddress!, count: buffer.count) } // int8Pointer.pointee == 1 // (int8Pointer + 3).pointee == 4 // After using 'int8Pointer': int8Pointer.deallocate() ``` After calling this method on a raw pointer `p`, the region starting at `p` and continuing up to `p + count * MemoryLayout.stride` is bound to type `T` and initialized. If `T` is a nontrivial type, you must eventually deinitialize or move from the values in this region to avoid leaks. The instances in the region `source..<(source + count)` are unaffected. --- 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)