range_checker is a derive-macro crate aimed to provide declarative bounds checking and filtering for structure.
```rust use range_checker::Check;
struct TestStruct { #[range(..=5)] #[range(20..)] #[filter(|x| x % 2 != 0)] #[fallback(255)] pub v0: u8, #[range(-1.0..=5.0)] #[fallback(3.1)] v1: f32, #[filter(|&x| x > 8.0)] #[fallback(9.9)] v2: f64, #[range(..-1)] #[fallback(|x| {println!("test fallback closure."); x - 5})] v3: isize, #[filter(|x:&str| !x.is_empty())] v4: String, }
fn main() { let a = TestStruct::default();
if let Ok(_) = a.check() {
todo!{}
}
} ```
Use #[range(...)]
to detemine the range for named struct's field.
Multiple #[range(...)]
will combined by ||
, which allowed to config any range you need.
Use #[filter(#closure)]
to filter for named struct's field, #closure: |#type_of_field| -> bool
.
Multiple #[filter(#closure)]
will combined by &&
.
#[filter(#closure)]
will combined with #[range(...)]
by &&
.
Active with the
fn check_with_callback()
Use #[fallback(#closure|#lit)]
to set fallback behavior for named struct's field, #closure: |#type_of_field| -> #type_of_field
.
One field brokes it's range or filter with fallback attribute setted, fn check_with_fallback()
will return Ok(_)
.
range_checker::Check
will return Err(())
immediately any field broke it's range or filter.
range_checker::CheckVerbose
will check all fields and return detail information like Err(Vec<Error>)
or Ok(Vec<Error>)
when all of broken fields has a fallback attribute.
Here(https://github.com/TYPEmber/rangechecker/tree/master/examples/expandcode.md) is an Expand Example for
```rust use rangechecker::Check; use rangechecker::CheckVerbose;
struct TestStruct { #[range(..=5)] #[range(20..)] #[filter(|x| x % 2 != 0)] #[fallback(255)] pub v0: u8, #[range(-1.0..=5.0)] #[fallback(3.1)] v1: f32, #[filter(|&x| x > 8.0)] #[fallback(9.9)] v2: f64, #[range(..-1)] #[fallback(|x| {println!("test fallback closure."); x - 5})] v3: isize, } ```