Make a new build tool: finn

[jparoz]

Separate out project management concerns into a build tool, which finds and prepares files according to some sort of project manifest, and then hands it all to huck. Similar to the separation between rustc and cargo.

Structuring this as a separate build tool means that different workflows can be customised as specifically as needed, but we can still provide a somewhat turnkey experience in general. The project manifest format should be able to be fairly flexible in the first place, but the build tool should technically be optional to use the language; i.e. the build tool should be replaceable without modifying the compiler.

Subcommands

• finn new
  • .gitignore ignoring /output
  • src directory
  • finn.yaml with sensible defaults
• finn build
• finn repl REPL #22
  • Should automatically bring all modules from the manifest into scope (qualified)
• finn test
  • What should this do? Testing framework #26
• finn add https://github.com/example/Module (adds a dependency to the manifest)
  • Need a version number?
  • Should this instead refer to some central package registry?

Features

• Package management
  • Probably using git repos as the hosting method
• Local file structure
  • Need to be able to specify (with sensible defaults) for each module:
    • input filepath (.hk file)
    • output filepath (generated .lua file)
    • input file directory (folder of .hk files)
    • output file directory (folder of generated .lua files)
  • Input file search strategies
    • All .hk files in a given subdirectory of the project folder
    • Every input filename specified manually
  • Output filename generation strategies
    • Each output next to its input file
    • All outputs in one big directory
    • Every output filename specified manually
• Make it possible to have no prelude #21