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+// Copyright (c) 2017 Gilad Naaman
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in all
+// copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+// SOFTWARE.
+
+//! A crate used for calculating offsets of struct members and their spans.
+//!
+//! This functionality currently can not be used in compile time code such as `const` or `const fn` definitions.
+//!
+//! ## Examples
+//! ```
+//! use memoffset::{offset_of, span_of};
+//!
+//! #[repr(C, packed)]
+//! struct HelpMeIAmTrappedInAStructFactory {
+//!     help_me_before_they_: [u8; 15],
+//!     a: u32
+//! }
+//!
+//! fn main() {
+//!     assert_eq!(offset_of!(HelpMeIAmTrappedInAStructFactory, a), 15);
+//!     assert_eq!(span_of!(HelpMeIAmTrappedInAStructFactory, a), 15..19);
+//!     assert_eq!(span_of!(HelpMeIAmTrappedInAStructFactory, help_me_before_they_ .. a), 0..15);
+//! }
+//! ```
+//!
+//! This functionality can be useful, for example, for checksum calculations:
+//!
+//! ```ignore
+//! #[repr(C, packed)]
+//! struct Message {
+//!     header: MessageHeader,
+//!     fragment_index: u32,
+//!     fragment_count: u32,
+//!     payload: [u8; 1024],
+//!     checksum: u16
+//! }
+//!
+//! let checksum_range = &raw[span_of!(Message, header..checksum)];
+//! let checksum = crc16(checksum_range);
+//! ```
+
+#![no_std]
+#![cfg_attr(
+    all(feature = "unstable_const", not(stable_const)),
+    feature(const_ptr_offset_from)
+)]
+#![cfg_attr(feature = "unstable_const", feature(const_refs_to_cell))]
+
+#[macro_use]
+#[cfg(doctests)]
+#[cfg(doctest)]
+extern crate doc_comment;
+#[cfg(doctests)]
+#[cfg(doctest)]
+doctest!("../README.md");
+
+/// Hidden module for things the macros need to access.
+#[doc(hidden)]
+pub mod __priv {
+    #[doc(hidden)]
+    pub use core::mem;
+    #[doc(hidden)]
+    pub use core::ptr;
+
+    /// Use type inference to obtain the size of the pointee (without actually using the pointer).
+    #[doc(hidden)]
+    pub fn size_of_pointee<T>(_ptr: *const T) -> usize {
+        mem::size_of::<T>()
+    }
+}
+
+#[macro_use]
+mod raw_field;
+#[macro_use]
+mod offset_of;
+#[macro_use]
+mod span_of;