Issue #19426 has been updated by matz (Yukihiro Matsumoto). I agree with moving nil comparison. Matz. ---------------------------------------- Bug #19426: Endless `Range#step` of object with `#succ` method does not work https://bugs.ruby-lang.org/issues/19426#change-101771 * Author: nobu (Nobuyoshi Nakada) * Status: Open * Priority: Normal * Backport: 2.7: REQUIRED, 3.0: REQUIRED, 3.1: REQUIRED, 3.2: REQUIRED ---------------------------------------- Consider this `c` object which hash `#succ` method. ```ruby c = Struct.new(:i) do def succ; self.class.new(i+1); end def <=>(other) i <=> other.i;end end.new(0) ``` This `Range#step` works. ```ruby (c..c.succ).step(1) do |d| p d.i # 0, 1 end ``` But it fails on an endless range. ```ruby (c..).step(1) do |d| p d.i break if d.i > 3 end ``` ``` -:3:in `<=>': undefined method `i' for nil:NilClass (NoMethodError) from -:10:in `step' from -:10:in `<main>' ``` -- https://bugs.ruby-lang.org/