# NVMAspects

**Repository Path**: mirrors_eleme/NVMAspects

## Basic Information

- **Project Name**: NVMAspects
- **Description**: No description available
- **Primary Language**: Unknown
- **License**: MIT
- **Default Branch**: master
- **Homepage**: None
- **GVP Project**: No

## Statistics

- **Stars**: 0
- **Forks**: 0
- **Created**: 2020-08-08
- **Last Updated**: 2026-05-23

## Categories & Tags

**Categories**: Uncategorized

**Tags**: None

## README

# NVMAspects

## About
Yet another AOP library for Objective-C, but implement by using [libffi](https://github.com/libffi/libffi/). The main goal for this lib is to avoid heavily use of `forwardInvocation`, powerful, easy to use and also easy to read.

This lib is inspired by [Aspects](https://github.com/steipete/Aspects), [JSPatch](https://github.com/bang590/JSPatch), [NSBlog](https://www.mikeash.com/pyblog/) and [sunnyxx's blog](http://blog.sunnyxx.com/archives/), thanks all these people.

## Example

A simple example is look like this, provide a block to replace the original implementation, look very similar to [Aspects](https://github.com/steipete/Aspects) but have a bit difference. You can alter the arguments or return value by modify `info.invocation`. If you aren't sure the existing of original implementation, you should call `class_addPlaceholderIfNoImplement` fisrt.

```objective-c
[[UIImage nvm_hookInstanceMethod:@selector(imageNamed:)
                      usingBlock:^void(NVMAspectInfo *info, NSString *name) {
                        NSLog(@"Load image named %@", name);
                        [info.invocation invoke];
                      }];
```

## Notes

- Actually there are some bugs on this lib, [Bit Field](https://github.com/eleme/NVMAspects/issues/3),  [Union](https://github.com/eleme/NVMAspects/issues/2), [Struct contain array](https://github.com/eleme/NVMAspects/issues/1). But `bit field` and `union` are also not well supportted by apple's `NSInvocation`, struct contain small array is a bug in `libffi`.  All these features used very rare in Objective-C,  so it's not a big problem.

- NVMAspects doesn't forbidden you to hook any method, but if you make some changes to method like `alloc`, you should follow the memory management policy, especially in `ARC`.

- Currently if a class has defined a method, hook this method will change it's `imp`, even if that method is implemented by it's super class. But this is not a big problem, you can distinguish the class by test `[self class]` in you block. If the class has not defined a method, you should call `class_addPlaceholderIfNoImplement` first.

- For problem caused by `forwardInvocation`, you can use this keyword to search issues in `Aspects` or `JSPatch`.

## Installation

add the following line to your Podfile:

```ruby
pod "NVMAspects"
```

## License

NVMAspects is released under the MIT license.