instance method

Object#<=>

(untyped other) -> 0?

self <=> other → 0 or nil

static VALUE
rb_obj_cmp(VALUE obj1, VALUE obj2)
{
    if (rb_equal(obj1, obj2))
        return INT2FIX(0);
    return Qnil;
}

Compares self and other.

Returns:

Examples:

Example

o = Object.new
o <=> o     # => 0
o <=> o.dup # => nil

A class that includes module Comparable should override this method by defining an instance method that:

Take one argument, other.
Returns:
- -1, if self is less than other.
- 0, if self is equal to other.
- 1, if self is greater than other.
- nil, if the two values are incommensurate.

See also #!~ #=== .yaml_tag #define_singleton_method also in 4.1 · 3.4 · 3.3 · 3.2 · 3.1 · 3.0