dc10

Definitional Compiler tools

• dc10-core: core models and abstractions for defining a language implementation
• dc10-io: fs2 integration for evaluating metaprograms into source files

examples

• dc10-scala: AST and dsl for defining and rendering Scala programs

---

dc10-core

• Library for Scala 3 (JS, JVM, and Native platforms)
• Bring your own AST

"com.julianpeeters" %% "dc10-core" % "0.4.0"

The compile package provides abstractions for implementation by a downstream language library:

Compiler

package dc10.compile

trait Compiler[
  F[_],              // Error functor in ctx
  G[_],              // Output unit, e.g., List, Id, etc.
  E,                 // Error type
  A,                 // Code level, representing symbols introduced into ctx
  B                  // File level, representing source files with path and ast
]:

  type Ctx[_[_],_,_] // Monadic context, to build up ASTs and then compile them

  extension [C, D] (ast: Ctx[F, List[D], C])
    def compile: F[List[D]]

  extension (res: F[G[A]])
    def toString[V](using R: Renderer[V, E, G[A]]): String

  extension (res: F[G[A]])
    def toStringOrError[V](using R: Renderer[V, E, G[A]]): F[String]

  extension (res: F[G[B]])
    def toVirtualFile[V](using R: Renderer[V, E, G[A]]): F[List[VirtualFile]]

Renderer

package dc10.compile

trait Renderer[V, E, A]:
  def render(input: A): String
  def renderErrors(errors: List[E]): String
  def version: V

VirtualFile

package dc10.compile

import java.nio.file.Path

case class VirtualFile(path: Path, contents: String)

dc10-io

• Library for Scala 3 (JVM only)
• Bring your own AST, compiler, and renderer implementations

"com.julianpeeters" %% "dc10-io" % "0.4.0"

The io package provides extension methods to write files using fs2:

FileWriter

extension [
  F[_]: Concurrent: Files,
  G[_]: Foldable,
  H[_],
  E,
  A,
  B
](res: G[H[B]])(using C: Compiler[G, H, E, A, B])
  def toFile[V](using R: Renderer[V, E, H[A]]): F[List[Path]] =
    C.toVirtualFile(res)
      .foldMapM(e => e.traverse(s => FileWriter[F].writeFile(s)))