std/equatable

Import with import std/equatable.

Exports

Interfaces

• Equatable

interface Equatable

interface Equatable {
    fn equal?(a: self, b: self): Bool
}

Protocol for structural equality between two values of the same type.

Equatable.equal?(a, b) returns True iff a and b are equal under the implementor’s notion of equality, and is always the explicit way to reach an implementor’s own equality.

The == operator is narrower: it routes through a registered Equatable.equal? for a struct type, and otherwise compares structurally without dispatching. So a hand-written impl on a struct overrides ==, while one on an enum, a distinct type or a primitive is reached by Equatable.equal? and by generic <T: Equatable> code but NOT by ==, which keeps the structural or direct-comparison path. != is the negation of whichever path == takes.

All four primitive types — Int, Float, Bool, String — implement Equatable using the underlying primitive equality. To implement it for a custom type:

pub struct Point {
  x: Int
  y: Int
}

impl Equatable for Point {
  fn equal?(a: Point, b: Point): Bool { a.x == b.x and a.y == b.y }
}

derive Equatable synthesizes pairwise field equality for structs, variant-then-payload comparison for enums, and inner-value delegation for distinct types.

Equatable.equal?

fn equal?(a: self, b: self): Bool

interface Equatable