Expand description
This library exports the auto_from
procedural attribute macro. It is used
to automatically generate std::convert::From
implementations for enum
variants containing only one field. It currently works for tuple or struct
variants. Here is a small example:
use auto_from::auto_from;
#[auto_from]
#[derive(Debug, PartialEq)]
enum Foo {
Int(i32),
Long { value: i64 },
}
assert_eq!(Foo::Int(24), Foo::from(24i32));
assert_eq!(Foo::Long{ value: 24 }, Foo::from(24i64));
This should be most useful when constructing error enums that require
writing many From
implementations, or using many
.map_error(|e| MyError::Variant(e))
calls across the code. This crate
just simplifies the process.