Crate bounded_types[−][src]
Expand description
Provides newtypes BoundedI32
, BoundedI64
, etc. which behave similar to their raw counterparts, but guarantee that the value is within a range that you specify.
In contrast to other crates like this, these types are implemented using the newly stabilized const generics feature, which allows for simplifications that make the use of this type more intuitive and idiomatic.
They are wrappers around a Result
, but implement traits like PartialEq<{Integer}>
and even Ord<{Integer}>
that make them act like integers in many ways. Some traits (like Add
, for example) are intentionally not implemented, since those would be invalid on out-of-bounds values.
Example
use bounded_types::BoundedI64; // If an in-bounds value is stored, comparisons behave like you would expect. let bounded_ok: BoundedI64<2, 10> = 5.into(); assert!(bounded_ok == 5); assert!(bounded_ok >= 5); assert!(bounded_ok >= 4); // you can compare with any integer assert!(bounded_ok < 100); assert!(bounded_ok > -100); // If an out-of-bounds value is stored, equal-checks and unequality-checks always return `false`. unequal-checks return true because ne() has to be the inverse of eq(). let bounded_err: BoundedI64<2, 10> = 11.into(); assert_eq!(bounded_err == 11, false); assert_eq!(bounded_err != 11, true); assert_eq!(bounded_err > 5, false);
Memory use
use bounded_types::*; use std::mem::size_of; assert!(size_of::<Option<i8>>() == size_of::<BoundedI8<0, 10>>()); assert!(size_of::<Option<i16>>() == size_of::<BoundedI16<0, 10>>()); assert!(size_of::<Option<i32>>() == size_of::<BoundedI32<0, 10>>()); assert!(size_of::<Option<i64>>() == size_of::<BoundedI64<0, 10>>()); assert!(size_of::<Option<i128>>() == size_of::<BoundedI128<0, 10>>()); // etc. you get the idea
Structs
BoundedI8 | An |
BoundedI16 | An |
BoundedI32 | An |
BoundedI64 | An |
BoundedI128 | An |
BoundedIsize | An |
BoundedU8 | An |
BoundedU16 | An |
BoundedU32 | An |
BoundedU64 | An |
BoundedU128 | An |
BoundedUsize | An |