Macro impl_display_with_writeable 

macro_rules! impl_display_with_writeable {
    (@display, $type:ty $(, where $($generics:tt)*)?) => { ... };
    ($type:ty $(, #[$alloc_feature:meta])? $(, where $($generics:tt)*)?) => { ... };
}

Implements Display for types that implement Writeable.

It’s recommended to do this for every Writeable type, as it will add support for core::fmt features like fmt!, print!, write!, etc.

This macro also adds a concrete to_string function. This function will shadow the standard library ToString, using the more efficient writeable-based code path. To add only Display, use the @display macro variant.

If your type has generics, list them in a where clause in the macro invocation.

Examples

use writeable::Writeable;
use std::fmt;

struct Message<T>(T);

impl<T> Writeable for Message<T> where T: Writeable {
    fn write_to<W: fmt::Write + ?Sized>(&self, sink: &mut W) -> fmt::Result {
        sink.write_str("Message: ")?;
        self.0.write_to(sink)
    }
    // ...
}

writeable::impl_display_with_writeable!(Message<T>, where T: Writeable);

writeable::assert_writeable_eq!(Message("hello"), "Message: hello");