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extern crate frunk_core;
extern crate frunk_proc_macros_impl;
extern crate proc_macro_hack;
use proc_macro_hack::proc_macro_hack;
#[proc_macro_hack]
pub use frunk_proc_macros_impl::path;
#[cfg(test)]
#[macro_use]
extern crate frunk;
#[cfg(test)]
mod tests {
#[test]
fn test_path() {
#[derive(LabelledGeneric)]
struct Dog<'a> {
name: &'a str,
dimensions: Dimensions,
}
#[derive(LabelledGeneric)]
struct Cat<'a> {
name: &'a str,
dimensions: Dimensions,
}
#[derive(LabelledGeneric)]
struct Dimensions {
height: usize,
width: usize,
unit: SizeUnit,
}
#[derive(Debug, Eq, PartialEq)]
enum SizeUnit {
Cm,
Inch,
}
let mut dog = Dog {
name: "Joe",
dimensions: Dimensions {
height: 10,
width: 5,
unit: SizeUnit::Inch,
},
};
let cat = Cat {
name: "Schmoe",
dimensions: Dimensions {
height: 7,
width: 3,
unit: SizeUnit::Cm,
},
};
let dimensions_lens = path!(dimensions);
let height_lens = dimensions_lens + path!(height);
let unit_lens = path!(dimensions.unit);
assert_eq!(*height_lens.get(&dog), 10);
assert_eq!(*height_lens.get(&cat), 7);
assert_eq!(*unit_lens.get(&dog), SizeUnit::Inch);
assert_eq!(*unit_lens.get(&cat), SizeUnit::Cm);
*height_lens.get(&mut dog) = 13;
assert_eq!(*height_lens.get(&dog), 13);
}
}