This is an interesting topic. I tried to benchmark these and sometimes local functions indeed show up as slightly slower, but it is typically in the 0~2% range even for this contrived example doing basically nothing. So I'm not sure if it is worth highlighting the difference: https://github.com/sabiwara/elixir_benches/commit/9b721f3b19f8af9d9d63a30618cdafeaa6367883
Checking the S file shows that external functions are just literals while local functions are calling make_fun3: https://github.com/sabiwara/elixir_benches/commit/9b721f3b19f8af9d9d63a30618cdafeaa6367883#diff-3a3b83d8acad1d3b6faed87ba471843f4424b22c26c179bf1d86a87a880e8223R74-R93 Even though, as far as I know, recent versions of Erlang have optimizations to make sure the overhead of lambdas like this one remains very small: https://github.com/erlang/otp/pull/6963. Le dim. 24 mars 2024 à 01:50, 'Rudolf Manusadzhian' via elixir-lang-core < elixir-lang-core@googlegroups.com> a écrit : > Hi there! Might be a naive question. > > Why don't we treat all local captures as external? Like at compile time, > if it's possible, we could treat *&fun/0* as *&__MODULE__.fun/0* and get > a free performance boost, if in the end they behave same. > > I was going thought the docs for :telemetry.attach/4 > <https://hexdocs.pm/telemetry/1.2.1/telemetry.html#attach/4> and the > suggestion to avoid using *local* captures raise that thought. > > If that's not possible, does it make sense to add a note in the docs > Kernel.SpecialForms.&/1 > # Capture > <https://hexdocs.pm/elixir/1.16.2/Kernel.SpecialForms.html#&/1-capture> about > the performance implications of local capture vs external or a > recommendation? > > Thanks. > > -- > You received this message because you are subscribed to the Google Groups > "elixir-lang-core" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to elixir-lang-core+unsubscr...@googlegroups.com. > To view this discussion on the web visit > https://groups.google.com/d/msgid/elixir-lang-core/c7065947-b48d-43e6-a450-387f6d4f1846n%40googlegroups.com > <https://groups.google.com/d/msgid/elixir-lang-core/c7065947-b48d-43e6-a450-387f6d4f1846n%40googlegroups.com?utm_medium=email&utm_source=footer> > . > -- You received this message because you are subscribed to the Google Groups "elixir-lang-core" group. To unsubscribe from this group and stop receiving emails from it, send an email to elixir-lang-core+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/elixir-lang-core/CANnyohZ_11fer8xQ4RTMbxv1WVgGHUuPTofoDinUA03Qys6ACw%40mail.gmail.com.
