#struct-fields #view #reference #derive #viewer #ref-view

macro refview_derive

Get a reference view of some fields into a struct

1 unstable release

0.1.0 Mar 6, 2022

#121 in #viewer


Used in refview

MIT/Apache

12KB
167 lines

ref-view

A derive macro that generates a "view" into some fields of a struct.

Usage

Motivation: easily generate a "Viewer" struct that has some fields that reference another struct.

Example input:

#[derive(RefView)]
struct DataStruct {
    field0: f64,
    field1: u64,
    field2: isize,
    field3: Vec<Box<usize>>,
}

This would (roughly) generate the following code:

pub struct DataStructViewer<'a> {
    pub field0: &'a f64,
    pub field1: &'a u64,
    pub field2: &'a isize,
    pub field3: &'a Vec<Box<usize>>,
}

impl<'a> RefView<'a> for DataStruct {
    type Viewer = DataStructViewer<'a>;
    fn view(&'a self) -> Self::Viewer
    where
        Self::Viewer: 'a,
    {
        Self::Viewer {
            field0: &self.field0,
            field1: &self.field1,
            field2: &self.field2,
            field3: &self.field3,
        }
    }
}

Mutable referenced structs can be generated with RefViewMut.

Planned features

  • Make some fields skip-able or include them though field attributes
  • More control over visability of generated struct

License

Licensed under either of Apache License, Version 2.0 or MIT license at your option.

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.

Dependencies

~1.5MB
~37K SLoC