Module: Comparable (Ruby 2.3.4)

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    • compar.c

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    Comparable

    The Comparable mixin is used by classes whose objects may be ordered. The class must define the <=> operator, which compares the receiver against another object, returning -1, 0, or +1 depending on whether the receiver is less than, equal to, or greater than the other object. If the other object is not comparable then the <=> operator should return nil. Comparable uses <=> to implement the conventional comparison operators (<, <=, ==, >=, and >) and the method between?.

    class SizeMatters
      include Comparable
      attr :str
      def <=>(other)
        str.size <=> other.str.size
      end
      def initialize(str)
        @str = str
      end
      def inspect
        @str
      end
    end
    
    s1 = SizeMatters.new("Z")
    s2 = SizeMatters.new("YY")
    s3 = SizeMatters.new("XXX")
    s4 = SizeMatters.new("WWWW")
    s5 = SizeMatters.new("VVVVV")
    
    s1 < s2                       #=> true
    s4.between?(s1, s3)           #=> false
    s4.between?(s3, s5)           #=> true
    [ s3, s2, s5, s4, s1 ].sort   #=> [Z, YY, XXX, WWWW, VVVVV]
    

    Public Instance Methods

    obj < other → true or false click to toggle source

    Compares two objects based on the receiver’s <=> method, returning true if it returns -1.

     
                   static VALUE
    cmp_lt(VALUE x, VALUE y)
    {
        VALUE c = rb_funcall(x, cmp, 1, y);
    
        if (rb_cmpint(c, x, y) < 0) return Qtrue;
        return Qfalse;
    }
                
    obj <= other → true or false click to toggle source

    Compares two objects based on the receiver’s <=> method, returning true if it returns -1 or 0.

     
                   static VALUE
    cmp_le(VALUE x, VALUE y)
    {
        VALUE c = rb_funcall(x, cmp, 1, y);
    
        if (rb_cmpint(c, x, y) <= 0) return Qtrue;
        return Qfalse;
    }
                
    obj == other → true or false click to toggle source

    Compares two objects based on the receiver’s <=> method, returning true if it returns 0. Also returns true if obj and other are the same object.

     
                   static VALUE
    cmp_equal(VALUE x, VALUE y)
    {
        VALUE c;
        if (x == y) return Qtrue;
    
        c = rb_exec_recursive_paired_outer(cmp_eq_recursive, x, y, y);
    
        if (NIL_P(c)) return Qfalse;
        if (rb_cmpint(c, x, y) == 0) return Qtrue;
        return Qfalse;
    }
                
    obj > other → true or false click to toggle source

    Compares two objects based on the receiver’s <=> method, returning true if it returns 1.

     
                   static VALUE
    cmp_gt(VALUE x, VALUE y)
    {
        VALUE c = rb_funcall(x, cmp, 1, y);
    
        if (rb_cmpint(c, x, y) > 0) return Qtrue;
        return Qfalse;
    }
                
    obj >= other → true or false click to toggle source

    Compares two objects based on the receiver’s <=> method, returning true if it returns 0 or 1.

     
                   static VALUE
    cmp_ge(VALUE x, VALUE y)
    {
        VALUE c = rb_funcall(x, cmp, 1, y);
    
        if (rb_cmpint(c, x, y) >= 0) return Qtrue;
        return Qfalse;
    }
                
    between?(min, max) → true or false click to toggle source

    Returns false if obj <=> min is less than zero or if anObject <=> max is greater than zero, true otherwise.

    3.between?(1, 5)               #=> true
    6.between?(1, 5)               #=> false
    'cat'.between?('ant', 'dog')   #=> true
    'gnu'.between?('ant', 'dog')   #=> false
    
     
                   static VALUE
    cmp_between(VALUE x, VALUE min, VALUE max)
    {
        if (RTEST(cmp_lt(x, min))) return Qfalse;
        if (RTEST(cmp_gt(x, max))) return Qfalse;
        return Qtrue;
    }