Allow context_name in enable_if #3566
Description
I think it would be very useful to allow context_name in enable_if rules: it will allow mirage to select which artefacts has to be installed on which context.
File "tutorial/noop/dune", line 16, characters 18-31:
16 | (enabled_if (= %{context_name} "mirage-spt"))
^^^^^^^^^^^^^
Error: Only architecture, system, model, os_type, ccomp_type, profile and
ocaml_version variables are allowed in this 'enabled_if' field. If you think
that context_name should also be allowed, please file an issue about it.