a build.tl file, to help generate code/run tools after code gen

[lenscas]

another thing that rust does that I started to like.

Instead of every library/program needing to setup their own tooling, rust checks for the existence of a build.rs file and if it exists it executes it, allowing it to generate code. As a result, pretty much every project uses the same commands to build/run. It also reduces the amount of tools that people need to know, as the build files are just rust. (Or in this case, will be teal)

I think that teal can do 1 better though by having the script return a table with the following entries and types
"run_on": {string}. A list of paths (paths can contain wildcards) that tell teal when to rerun the script. Otherwise, the previous output can be used.
"before_compile": function(out_dir:string) .A function to run before compiling. out_dir is the path where it should store the generated files.
"after_compile": function(build_dir:string). A function to run after the code has been generated. This one only runs when using tl build or tl run and is not affected by the paths given in "run_on". This allows you to run tools on the code.

If this is implemented then the compiler might be able to replace the current make script for a build.tl file, allowing people to work on it like a normal project . It also makes integrating tools easier, #67 can then be done through these build files, instead of either project needing to write code to support each other. (Just have an after_compile function that executes luapak)

Other examples can be a library like https://github.com/adelsz/pgtyped but without the need to manual run the command

or, in my own project where I already had to generate code for lua, and with the switch to teal I also need to automatically generate some of its types. So having teal run the correct commands for me would be appreciated :)

I don't mind opening a PR for this, I'm actually already playing with the teals codebase.

[hishamhm]

Reviewing old open issues — this has been initially implemented by tl build and later superseded by script support in cyan build, right? I guess we can close this one, then?

[lenscas]

Yep