3 releases
0.1.2 | Jan 13, 2024 |
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0.1.1 | Mar 21, 2023 |
0.1.0 | Sep 10, 2022 |
#27 in #fallback
81 downloads per month
Used in 5 crates
(via fallback)
7KB
108 lines
fallback
This is a helper library to implement fallback mechaism.
It contains two Option
, and if the "desired" one is None
, the "base" one will be chosen.
A trait called FallbackSpec
is used to implement field fallback for a struct.
use fallback::*;
#[derive(FallbackSpec)]
struct Foo {
data1: i32,
data2: String,
}
let data = Foo {
data1: 123,
data2: "Hello".to_string(),
};
let data = Fallback::new(None, Some(data));
let data = data.spec();
assert_eq!(data.data1.unzip(), (None, Some(123)));
assert_eq!(data.data2.unzip(), (None, Some("Hello".to_string())));
Dependencies
~245–690KB
~16K SLoC