Library offering an easy access Python like decorators in rust
Via this library we can easily alter the content of a defined function, by injecting code to be executed before/after the original function, without altering the original function itself.
For example, let's assume that we are interested on logging the duration of the execution of a function.
fn function_to_be_decorated() -> usize {
# let do_something_expensive = || 1234;
do_something_expensive()
}
In order to achieve so we would need to manually modify it similarly to
fn function_to_be_decorated() -> usize {
# let do_something_expensive = || 1234;
let start = std::time::Instant::now();
let return_value = do_something_expensive();
println!("Duration of function_to_be_decorated is: {}ms", start.elapsed().as_millis());
return_value
}
As far as this could be very simple, it is tedious and requires to actually modify the original function. While having a simple decorator that would do it for us would be much more convenient. Leading to something like
# use context_manager::SyncWrapContext;
# struct PrintDuration;
# impl<T> SyncWrapContext<T> for PrintDuration { fn new() -> Self { Self } }
#[context_manager::wrap(PrintDuration)]
fn function_to_be_wrapped() -> usize {
# let do_something_expensive = || 1234;
do_something_expensive()
}The library exposes 2 main traits that allows users to customize the wrapping logic
- [
SyncWrapContext] for synchronous context management (which is supported for decorating sync and async functions) - [
AsyncWrapContext] for asynchronous context management (which is supported ONLY for async functions)
and 2 main attribute macros ([wrap] and [async_wrap]) that allow an easy plug-and-play of the logic into the code
Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in this crate by you, as defined in the Apache-2.0 license, shall be dual licensed as above, without any additional terms or conditions.