rl'

rlp (ruelang') will be a lazily-evaluated purely-functional language heavily imitating Haskell.

Build Info

• rlp is built using Cabal
• rlp's documentation is built using Sphinx

$ cabal build       # Build the rlpc compiler
$ cabal install     # Install rlpc to $PATH
$ cabal haddock     # Build the API docs w/ Haddock
$ make -C doc html  # Build the primary docs w/ Sphinx

# run the test suite
$ cabal test --test-show-details=direct

Use

# Compile and evaluate examples/factorial.hs, with evaluation info dumped to stderr
$ rlpc -ddump-eval examples/factorial.hs
# Compile and evaluate t.hs, with evaluation info dumped to t.log
$ rlpc -ddump-eval -l t.log t.hs
# Print the raw structure describing the compiler options
# (option parsing still must succeed in order to print)
$ rlpc -ddump-opts t.hs

Potential Features

Listed in order of importance.

• ADTs
• First-class functions
• Higher-kinded types
• Typeclasses
• Parametric polymorphism
• Hindley-Milner type inference
• Newtype coercion
• Parallelism

Milestones

(This list is incomplete.)

• Backend
  • Core language
    • AST
  • Low-level execution model (TI)
    • Arithmetic
    • Conditionals
    • Structured data
    • Garbage collection
  • Low-level execution model (GM)
    • Arithmetic
    • Conditionals
    • Structured data
    • Garbage Collection
  • Emitter
    • Code-gen (target yet to be decided)
  • Core linter (Type-checker)
  • Core2Core pass (optimisations and misc. preprocessing)
    • GM prep
      • Non-strict case-floating
    • Let-floating
    • TCO
    • DCE
• Frontend
  • High-level language
    • AST
    • Lexer
    • Parser
  • Translation to the core language
    • Constraint solver
    • do-notation
  • CLI
• Documentation
  • State transition rules
  • How does the evaluation model work?
  • The Hindley-Milner type system
  • CLI usage
  • Tail call optimisation
  • Parsing rlp
  • Trees That Grow
• Tests
  • Generic example programs
  • Parser

December Release Plan

• Tests
  • Core lexer
  • Core parser
  • Evaluation model
• Benchmarks
• Stable Core lexer
• Stable Core parser
• Stable evaluation model
  • Garbage Collection
• Stable documentation for the evaluation model

January Release Plan

• Beta rl' to Core
• UX improvements
  • Actual compiler errors -- no more unexceptional error calls
  • Better CLI dump flags
  • Annotate the AST with token positions for errors (NOTE: As of Feb. 1, this has been done, but the locational info is not yet used in error messages)
• More examples

March Release Plan

• Tests
  • rl' parser
  • rl' lexer

Indefinite Release Plan

This list is more concrete than the milestones, but likely further in the future than the other release plans.

• Stable rl' to Core
• Core polish
  • Better, stable parser
  • Better, stable lexer
  • Less hacky handling of named data
  • Less hacky pragmas
• GM to LLVM