Issue #19737 has been updated by Eregon (Benoit Daloze). Could you include your actual concrete use case? See https://github.com/ruby/ruby/wiki/How-To-Request-Features Regarding naming, `cat` or `concat` feels wrong, `+` seems a much better match for the proposed semantics (no mutation). I'm unsure if it's a good idea to concatenate IO::Buffer's, maybe it's not really meant for that, and it wouldn't be particularly fast. Maybe it's easy to workaround by converting to String first for the probably-rare cases it's needed? ---------------------------------------- Feature #19737: Add `IO::Buffer#cat` for concat `IO::Buffer` instances https://bugs.ruby-lang.org/issues/19737#change-103601 * Author: unasuke (Yusuke Nakamura) * Status: Open * Priority: Normal ---------------------------------------- ## motivation In my use case, I want to concat two IO::Buffer instances. But current implementation doesn't have that way. Then I created a patch. Opend here: TBD ## concern I have two concerns about it. ### 1. Should we provide `IO::Buffer#+` as an alias? In String instance, `"a" + "b"` returns `"ab",`. It feels intuitive. So, should we provide the same way as `IO::Buffer.for("a") + IO::Buffer.for("b")`? If `+` is provided, I naturally assume that `*` is also provided as an operator. Should we also provide an `IO::Buffer#*` method for symmetry with the String class? I thought the behavior of the "*" method is not obvious to me... (Is it right to just return joined buffers?) ### 2. Should it accept multiple IO::Buffer instances? In the `cat` command, it accepts multiple inputs like this. ``` $ cat a.txt b.txt c.txt a b c ``` Should `IO::Buffer#cat` accept multiple inputs too? -- https://bugs.ruby-lang.org/