Translating Go

This Haskell project implements translations from Featherweight (Generic) Go to various target languages.

• There is a syntax-directed translation from FG to Haskell.
• There is a type-directed translation from FGG to Racket (untyped target language).

Usage

This project assumes that you use the stack tool for compiling and running the translation. (Using cabal should be possible but was not tested.)

• Compile: stack build
• Test: stack test
• Install: stack install
• Run without installation:
  • stack run -- FILE.go
  • Or use the script ./gotrans FILE.go in the toplevel directory (requires bash and some sort of unix system)
• Run with installation: gotrans FILE.go (make sure stack's installation directory is in your path)

Running the translation for input file FILE.go produces either the Haskell file FILE.hs or the racket file FILE.rkt. Load the Haskell file into ghci, for example via stack exec ghci -- FILE.hs, and then invoke the main function by typing main at the ghci prompt. Just run the racket file via racket FILE.rkt.

Important list of commandline options

• To use the same syntax for generics as Go, use the --modern commandline switch. Type arguments are then put in square brackets [...].
• Type-directed translation to Racket: --type (without generics) or --type-generic.
• Syntax-directed transaltion to Haskell (no support for generics): --syntax

Full list of commandline options:

Usage: gotrans [--target ARG] [--no-casts] [--trace] FILE [--modern]
  Translations from Featherweight (Generic) Go to various target languages

Available options:
  --target ARG             The target ('parse', 'parse-generic', 'syntax', 'type', 'type-generic')
  --no-casts               Do not translate casts
  --trace                  Enable tracing
  --modern                 Use modern syntax for generics
  -h,--help                Show this help text

Source Language

The source language is Featherweight Go with the following additions:

• Support for builtin types int, char, bool, and string.
• Support for type definitions
• Import of "fmt" is allowed.
• The main function may declare a sequence of variables and than perform a fmt.Printf
• There might be several "main" functions, named main, main0, main1, main2 and so on.
• The translation accepts pragmas of the form //#import FILE.go for literally including all declarations in FILE.go

Target language: Haskell

The output of the syntax-directed translation in Haskell with several language extension as accepted by GHC. The language extension are included as pragmas in the output.

Papers

Martin Sulzmann and Stefan Wehr Semantic preservation for a type directed translation scheme of Featherweight Go In Proc. of MPC 2022. Lecture Notes in Computer Science, vol. ?, Chicago, IL, USA. SPRINGER, 2022. arxiv

Martin Sulzmann and Stefan Wehr A Dictionary-Passing Translation of Featherweight Go In Proc. of APLAS 2021. Lecture Notes in Computer Science, vol. 13008, Chicago, IL, USA. SPRINGER, 2021. arxiv