memoffset
C-Like offset_of functionality for Rust structs.
Introduces the following macros:
offset_of!for obtaining the offset of a member of a struct.offset_of_tuple!for obtaining the offset of a member of a tuple. (Requires Rust 1.20+)offset_of_union!for obtaining the offset of a member of a union.span_of!for obtaining the range that a field, or fields, span.
memoffset works under no_std environments.
If you're using a rustc version greater or equal to 1.77, this crate's offset_of!() macro simply forwards to core::mem::offset_of!().
Usage
Add the following dependency to your Cargo.toml:
[]
= "0.9"
These versions will compile fine with rustc versions greater or equal to 1.19.
Examples
use ;
Usage in constants
memoffset has support for compile-time offset_of! on rust>=1.65.
On versions below 1.77, this is an incomplete implementation with one caveat:
Due to dependence on #![feature(const_refs_to_cell)], you cannot get the offset of a Cell field in a const-context.