4 releases (breaking)
|0.3.0||Apr 8, 2022|
|0.2.0||Sep 11, 2020|
|0.1.0||Sep 10, 2020|
|0.0.0||Sep 8, 2020|
#42 in macOS and iOS APIs
29 downloads per month
Rusty bindings for Apple libraries, brought to you by @NikolaiVazquez.
If this project is useful to you, consider sponsoring me or donating directly!
Doing so enables me to create high-quality open source software like this. ❤️
This library is available on crates.io and can be used in your project
by adding the following to your project's
[dependencies.fruity] version = "0.3.0"
Each module for a library or framework has its own feature flag with the same name.
For example, this is how you enable the
[dependencies.fruity] version = "0.3.0" features = ["foundation"]
This feature transitively enables the
Fruity makes interfacing with these C and Objective-C APIs feel natural in Rust.
Automatic Reference Counting.
Fruity takes advantage of Rust's ownership model to handle object reference counting for you.
NSObjectis a smart pointer that calls
Drop. This is exactly how Rust's
In Objective-C, all objects are nullable unless marked with
_Nonnull. This often leads to either very defensive checks or careless ignoring of null objects.
Fruity reverses that and instead makes all objects (such as
NSObject) non-null by default. An object can be made nullable by wrapping it with
To make FFI safe and easy, the following Objective-C and Rust types are ABI-compatible:
NSObject * _Nonnulland
NSObject * _Nullableand
This is because
#[repr(transparent)]wrapper around a
In Objective-C, methods take a pointer to where an
NSErroris placed upon failure. This makes it easy to avoid error handling and assume the happy path, which can lead to bugs when errors occur.
Fruity instead returns a
Result, which is the canonical way to handle errors in Rust. This ensures that errors must be acknowledged in some way.
Most of these types are classes that inherit from each other. Because true inheritance is not possible in Rust, Fruity uses
Derefto model Objective-C subclassing.
DispatchQueuehave many configurable inputs to create an instance. Many of these inputs have standard default values, so it is cumbersome to specify them all each time. Swift solves this by having default parameters in
init. However, Rust does not have default function parameters.
Fruity instead solves this using the builder pattern. See
DispatchQueueBuilderas an example. This reduces and simplifies code for creating dispatch queues.
Using Fruity to interface with Objective-C libraries should have as little runtime cost as writing the same code directly in Objective-C.
This is true for the following:
Calling object methods.
Method dispatch is always direct and does not need the error checking overhead of other wrappers that use the
objc::msg_send!macro. This also reduces the size of your program by not emitting panics that would otherwise never get called.
This library is carefully written to ensure that calls to
objc_msgSendare always done with the correct object type, method selector, and arguments.
Getting a static class.
NSString::classretrieve the class directly through its symbol. This is instantaneous, especially when compared to calling into the Objective-C runtime via
NSStringfrom a Rust string literal.
nsstring!macro creates an
@"string") at compile time. There is no runtime dispatch/allocation/initialization cost.
Some parts of this library still aren't zero cost. Your help would be much appreciated here!
selector!macro. See issue #2 for details.
This project is released under either the MIT License or Apache License (Version 2.0), at your choosing.