Issue #20337 has been updated by jeremyevans0 (Jeremy Evans). I submitted a pull request to fix this: https://github.com/ruby/ruby/pull/11657 ---------------------------------------- Bug #20337: Complex#inspect mutates the string returned by `real.inspect` https://bugs.ruby-lang.org/issues/20337#change-109883 * Author: Eregon (Benoit Daloze) * Status: Open * ruby -v: ruby 3.2.2 (2023-03-30 revision e51014f9c0) [x86_64-linux] * Backport: 3.0: UNKNOWN, 3.1: UNKNOWN, 3.2: UNKNOWN, 3.3: UNKNOWN ---------------------------------------- ``` irb(main):001:0> n = Numeric.new => #<Numeric:0x00007f81b2308578> irb(main):004:0> class Numeric; def inspect = super.freeze; end => :inspect irb(main):006:0> Complex(n, 1).inspect (irb):6:in `inspect': can't modify frozen String: "#<Numeric:0x00007f81b2308578>" (FrozenError) from (irb):6:in `<main>' from /home/eregon/.rubies/ruby-3.2.2/lib/ruby/gems/3.2.0/gems/irb-1.6.2/exe/irb:11:in `<top (required)>' from /home/eregon/.rubies/ruby-3.2.2/bin/irb:25:in `load' from /home/eregon/.rubies/ruby-3.2.2/bin/irb:25:in `<main>' ``` It feels wrong to mutate the result of inspect at least in general, for instance `true.inspect` is frozen. Discovered by https://github.com/ruby/spec/pull/1142 -- https://bugs.ruby-lang.org/