plug_app example doesn't compile w/Elixir 1.18.4

[rlipscombe]

Specifically, this line:

        name: %Schema{type: :string, description: "User name", pattern: ~r/[a-zA-Z][a-zA-Z0-9_]+/},

results in this error:

== Compilation error in file lib/plug_app/schemas.ex ==
** (ArgumentError) cannot inject attribute @schema into function/macro because cannot escape #Reference<0.3066655214.653918209.71876>. The supported values are: lists, tuples, maps, atoms, numbers, bitstrings, PIDs and remote functions in the format &Mod.fun/arity
    (elixir 1.18.4) lib/kernel.ex:3777: Kernel.do_at_escape/2
    (elixir 1.18.4) expanding macro: Kernel.@/1
    lib/plug_app/schemas.ex:6: PlugApp.Schemas.User.schema/0

[jfpedroza]

That's more of an Erlang OTP 28 problem. It works with Elixir 1.18 and OTP 27. To avoid refactoring, you should use OTP 28 with Elixir 1.19 which does allow putting regexes in module attributes.