Overview of Comparison Operators

Equality operators return BOOL; the three-way operator <=> returns ORDER::LESS, ORDER::EQUAL, or ORDER::GREATER.

VAR low I32 := 2;
VAR high I32 := 5;

ASSERT(low != high);
ASSERT(low < high);
ASSERT(low <= high);
ASSERT((low <=> high) == ORDER::LESS);

Three-way comparison

<=> is useful when code needs the relationship itself:

VAR relationship ORDER := left <=> right;
IF (relationship == ORDER::GREATER)
{
  use_right_first();
}

User-defined types can provide .OPERATOR<=>; Quxlang derives <, >, <=, and >= from its ORDER result.

::coordinate STRUCT
{
  .value VAR I32;

  .OPERATOR<=> FUNCTION(@OTHER CONST& coordinate): ORDER
  {
    RETURN .value <=> OTHER.value;
  }
}

A user-defined .OPERATOR== expresses an equality contract directly. Quxlang derives != by negating equality.

Comparable categories

Primitive numbers, BOOL, enums, flagsets, type indexes, addresses, compatible pointers, arrays, and eligible structural values provide built-in or generated comparison. Floating-point operators use Quxlang's strong total ordering. Polymorphic structs do not receive generated comparison; see Inheritance.

Reference

See the Comparison Operators Reference for supported categories, overload dispatch order, generated lexicographic comparison, pointer constraints, and floating-point ordering boundaries.