obj < other    → true or false

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

Source Code

/*
*  call-seq:
*     obj < other    => true or false
*  
*  Compares two objects based on the receiver's <code><=></code>
*  method, returning true if it returns -1.
*/

static VALUE
cmp_lt(x, y)
   VALUE x, y;
{
   VALUE c = rb_funcall(x, cmp, 1, y);

   if (NIL_P(c)) return cmperr();
   if (rb_cmpint(c, x, y) < 0) return Qtrue;
   return Qfalse;
}