Enhance include to depend on generated files, rather than on ones in the source tree

[maxim092001]

Desired Behavior

According to current documentation:

Currently, the included file cannot be generated and must be present in the source tree.

It is a common use case for user to create OCaml executable that would generate a dune.inc.gen file and then include it into the dune file.

More about other use cases in official dune guide.

My current understanding is that include happens before rule generation. As a user, one may expect dune to regenerate generated file for me first before including it. Currently, I have to run dune build twice:

• First build to generate new dune.inc.gen
• Second build to pick up new dune.inc.gen

There are multiple approaches we can take, I am not sure what is the best one, so will list couple:

• Add deps to include stanza to have ability to depend on some generated file/alias
• Create include-gen stanza that would expect file to be generated by rules, rather than picking it up from source tree
  • It would probably run all rules before include and then run included rules

Example

Examples in official dune guide that have current behavior.

Thanks!

[nojb]

Hello, note that this is already supported, using the dynamic_include stanza: https://dune.readthedocs.io/en/latest/reference/dune/dynamic_include.html.

[maxim092001]

Hello, note that this is already supported, using the dynamic_include stanza: https://dune.readthedocs.io/en/latest/reference/dune/dynamic_include.html.

Great! Thanks Nicolas!

Then I propose to just add a link to dynamic_include from include in documentation. Would that make sense?

Replace

Currently, the included file cannot be generated and must be present in the source tree.

With

Currently, the included file cannot be generated and must be present in the source tree. To use generated include file please refer to dynamic_include

[nojb]

Then I propose to just add a link to dynamic_include from include in documentation. Would that make sense?

Yes, this would be a good idea. Thanks.