objc-encode - Objective-C type-encoding in Rust

The Objective-C directive @encode encodes types as strings for usage in various places in the runtime.

This crate provides the Encoding type to describe and compare these type-encodings without memory allocation.

Additionally it provides traits for annotating types that has a corresponding Objective-C encoding, respectively Encode for structs and RefEncode for references (and EncodeArguments for function arguments).

These types are exported under the objc crate as well, so usually you would just use that crate.

Examples

Implementing Encode and RefEncode:

```rust use objc_encode::{Encode, Encoding, RefEncode};

[repr(C)]

struct MyObject { a: f32, b: bool, }

unsafe impl Encode for MyObject { const ENCODING: Encoding<'static> = Encoding::Struct( "MyObject", &[f32::ENCODING, bool::ENCODING ]); }

assert_eq!(&MyObject::ENCODING, "{MyObject=fB}");

unsafe impl RefEncode for MyObject { const ENCODING_REF: Encoding<'static> = Encoding::Pointer(&Self::ENCODING); }

asserteq!(&MyObject::ENCODINGREF, "^{MyObject=fB}"); ```

An Encoding can be compared with an encoding string from the Objective-C runtime:

rust use objc::Encode; assert!(&i32::ENCODING == "i");

Encoding implements Display as its string representation. This can be generated conveniently through the to_string method:

rust use objc::Encode; assert_eq!(i32::ENCODING.to_string(), "i");

See the [examples] folder for more complex usage.

Installation

toml [dependencies] objc-encode = "1.1.0"

License

This project is licensed under the MIT license, see [../LICENSE.txt].

Work is in progress to make it dual-licensed under the Apache License (Version 2.0) as well.