GSoC: Integration of libSyntax with the rest of the compiler pipeline

[rintaro (Rintaro Ishizaki)]

Hi Vinicius,

Thank you for being interested in this project!
Just FYI, there's another discussion about this project: [GSOC]Integration of libSyntax with the rest of the compiler pipeline

@harlanhaskins

My personal, super ambitious goal for libSyntax is to reformulate the compiler pipeline from

          -> AST (with syntactic bits) -> Typechecked AST -> SIL -> ... -> Binary
<source> |
          -> libSyntax AST

to

<source> -> libSyntax AST -> Semantic AST (with no syntactic bits, pointing back to libSyntax) -> Typechecked Semantic AST -> SIL -> ... -> Binary`

That’s my personal dream.

And so is mine
In addition to this, we want to input serialized libSyntax tree (JSON) directly to the compiler.

Since it's super ambitious, I don't think we fully finish this work and merge into the repo in this GSoC timeframe. But I believe we should eventually do this. In your proposal, I expect you to plan what you will finish in the timeframe, and what you will not.

Roughly, we should do:

• Implement a parser to parse only into libSyntax tree.
• Modify AST nodes to hold libSyntax nodes for source information (getLoc() etc.)
• Implement a libSyntax tree to AST translator. This should do:
  • Everything the current parser do:
    • Diagnostics
    • Name binding
    • Resolve #if config
    • Code completion
  • (Hopefully) Move some feature from Sema:
    • Resolve import
    • Fold sequence expression (Resolve operator precedence)
    • Resolve type expression
• Make a way to input serialized libSyntax tree to the compiler