pub trait SubsetOf<T>: Sized {
// Required methods
fn to_superset(&self) -> T;
fn from_superset_unchecked(element: &T) -> Self;
fn is_in_subset(element: &T) -> bool;
// Provided method
fn from_superset(element: &T) -> Option<Self> { ... }
}Expand description
Nested sets and conversions between them (using an injective mapping). Useful to work with
substructures. In generic code, it is preferable to use SupersetOf as trait bound whenever
possible instead of SubsetOf (because SupersetOf is automatically implemented whenever
SubsetOf is).
The notion of “nested sets” is very broad and applies to what the types are supposed to represent, independently from their actual implementation details and limitations. For example:
- f32 and f64 are both supposed to represent reals and are thus considered equal (even if in practice f64 has more elements).
- u32 and i8 are respectively supposed to represent natural and relative numbers. Thus, u32 is a subset of i8.
- A quaternion and a 3x3 orthogonal matrix with unit determinant are both sets of rotations. They can thus be considered equal.
In other words, implementation details due to machine limitations are ignored (otherwise we could not even, e.g., convert a u64 to an i64). If considering those limitations are important, other crates allowing you to query the limitations of given types should be used.
Required Methods§
sourcefn to_superset(&self) -> T
fn to_superset(&self) -> T
The inclusion map: converts self to the equivalent element of its superset.
sourcefn from_superset_unchecked(element: &T) -> Self
fn from_superset_unchecked(element: &T) -> Self
Use with care! Same as self.to_superset but without any property checks. Always succeeds.
sourcefn is_in_subset(element: &T) -> bool
fn is_in_subset(element: &T) -> bool
Checks if element is actually part of the subset Self (and can be converted to it).
Provided Methods§
sourcefn from_superset(element: &T) -> Option<Self>
fn from_superset(element: &T) -> Option<Self>
The inverse inclusion map: attempts to construct self from the equivalent element of its
superset.
Must return None if element has no equivalent in Self.