kframework / haskell-core-semantics

Haskell's Core in K.

GHC Core in K

Our ongoing work on the implementation of GHC's Core language lives in this repository.

Running

Prerequisites

First make sure that you have K (latest release) as well as Haskell Stack installed. Then:

• Run make in the root of the repository.
• Run stack install inside compile-to-core. This will build and install our tool that converts Haskell programs into an intermediate representation of of Haskell Core. To find out how to experiment with this tool, you can run to-core --help.

Running Haskell

You can use script/krunhaskell.sh to directly run Haskell code. First run source setup.sh to configure the environment variable HASKELL_CORE_SEMANTICS_DIR that will be needed. This will also alias krunhaskell to the absolute path of script/krunhaskell.sh so that you can use it anywhere.

In a Haskell file Foo.hs that you want to run, designate an expression by adding a top-level declaration with the definiendum result; the definiens of this declaration is the expression whose evaluation will be forced. For example, Foo.hs might look like:

module Foo where

result = (\x -> \y -> (\x -> x) x) 3 5

Then running

krunhaskell Foo

yields

<k> lit ( litInt ( 3 , [type omitted] ) ) </k>

which is what the result of running the Core program generated by Foo.hs throught the Core semantics is. Our concrete representation of GHC Core is documented here.