Protocol std::cmp::Comparable

Types that have a total order.

Types that implement this protocol can be compared using the <, <=, > and >= operators.

Method compare must be implemented, other methods can be mixed in. This includes the default implementations for equals and not_equals of the Equatable protocol.

Example

struct FullName { first: &[u8], last: &[u8] }

impl FullName {
    use std::cmp::{Ordering, Comparable};

    fn new(first: &[u8], last: &[u8]) -> FullName {
        FullName { first: first, last: last }
    }

    fn compare(self: &FullName, other: &FullName) -> Ordering {
        let first_cmp = self.first.compare(&other.first);
        if first_cmp != Ordering::Equal {
            return first_cmp;
        }
        self.last.compare(&other.last)
    }

    mixin Comparable<FullName>;
}

assert!(FullName::new("John", "Malkovich") < FullName::new("John", "McCain"));
assert!(FullName::new("John", "Doe") == FullName::new("John", "Doe"));
Run this example

See also lex_compare for a convenient way to implement the compare method.

Required methods

• fn compare(lhs: &Self, rhs: &Self) -> Ordering

  source

  Compare the value

  See Comparable for details.

Provided methods

• fn equals(lhs: &Self, rhs: &Self) -> bool

  source

  Returns true if lhs is equal to rhs, false otherwise

• fn not_equals(lhs: &Self, rhs: &Self) -> bool

  source

  Returns true if lhs not equal to rhs, false otherwise

• fn less_than(lhs: &Self, rhs: &Self) -> bool

  source

  Returns true if lhs is strictly less than rhs, false otherwise

• fn less_than_or_equal(lhs: &Self, rhs: &Self) -> bool

  source

  Returns true if lhs is less or equal to rhs, false otherwise

• fn greater_than(lhs: &Self, rhs: &Self) -> bool

  source

  Returns true if lhs strictly greater than rhs, false otherwise

• fn greater_than_or_equal(lhs: &Self, rhs: &Self) -> bool

  source

  Returns true if lhs greater than or equal rhs, false otherwise