objc2-encode

Objective-C type-encoding in Rust.

This crates provides types to parse and compare Objective-C type-encodings created with the @encode directive.

See the docs for a more thorough overview.

This crate is part of the objc2 project, see that for related crates.

lib.rs:

Objective-C type-encoding

The Objective-C directive @encode encodes types as strings, and this is used in various places in the runtime.

This crate provides the [Encoding] type to describe and compare these type-encodings, and the [EncodingBox] type which does the same, except it can be parsed from an encoding at runtime.

The types from this crate is exported under the objc2 crate as objc2::encode, so usually you would just use it from there.

Example

Parse an encoding from a string and compare it to a known encoding.

use objc2_encode::{Encoding, EncodingBox};
let s = "{s=i}";
let enc = Encoding::Struct("s", &[Encoding::Int]);
let parsed: EncodingBox = s.parse()?;
assert!(enc.equivalent_to_box(&parsed));
assert_eq!(enc.to_string(), s);
# Ok::<(), objc2_encode::ParseError>(())

Further resources

• Objective-C, Encoding and You.
• Apple's documentation on Type Encodings.
• How are the digits in ObjC method type encoding calculated?
• clang's source code for generating @encode.