5 releases (breaking)
0.5.0 | Oct 20, 2022 |
---|---|
0.4.0 | Sep 12, 2022 |
0.3.2 |
|
0.3.0 | Oct 4, 2021 |
0.1.0 | Apr 25, 2021 |
#10 in #stylish
74 downloads per month
Used in valued
27KB
585 lines
Giftwrap
Wrap and unwrap your types the stylish way with derive macros for From/TryFrom in both directions
How does it work?
giftwrap
exposes two derive macros, Wrap
and Unwrap
that derive impl From<inner_type> for your_type
and impl From<your_type> for inner_type
(or TryFrom<your_type>
in the case of enums) respectively.
It works for any struct or enum variant that holds only a single type, and don't worry variants with multiple types or with types you want to convert yourself can be easily ignored by setting noWrap
and noUnwrap
in the #[giftwrap()]
attribute.
Examples
Consider the following error.rs
pub type Result<T> = std::result::Result<T, Error>;
macro_rules! impl_from {
($wrapper:expr, $inner:ty) => {
impl From<$inner> for Error {
fn from(e: $inner) -> Error {
$wrapper(e)
}
}
};
}
#[derive(Debug)]
pub enum Error {
Io(std::io::Error),
RppalGpio(rppal::gpio::Error),
Reqwest(reqwest::Error),
Qr(Box<qrcodegen::DataTooLong>),
Other(String),
}
impl_from!(Error::Io, std::io::Error);
impl_from!(Error::RppalGpio, rppal::gpio::Error);
impl_from!(Error::Reqwest, reqwest::Error);
impl From<qrcodegen::DataTooLong> for Error {
fn from(f: qrcodegen::DataTooLong) -> Self {
Error::Qr(f.into())
}
}
impl From<Box<qrcodegen::DataTooLong>> for Error {
fn from(f: Box<qrcodegen::DataTooLong>) -> Self {
Error::Qr(f)
}
}
This might seem simple enough but adding new error types is not as easy as it could be.
However with giftwrap
it's as simple as it gets:
pub type Result<T> = std::result::Result<T, Error>;
use giftwrap::Wrap;
#[derive(Debug, Wrap)]
pub enum Error {
Io(std::io::Error),
RppalGpio(rppal::gpio::Error),
Reqwest(reqwest::Error),
#[giftwrap(wrapDepth = 0)]
Qr(<qrcodegen::DataTooLong>),
#[giftwrap(noWrap = true)]
Other(String),
}
Now you could add a new error variant wrapping a type from any library and giftwrap
handles the rest for you
Dependencies
~2MB
~46K SLoC