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Tests Cabal

This package provides a Haskell wrapper for the QuickJS Javascript Engine. It has been inspired by the quickjs-rs and ocaml-quickjs libraries.


The functionality is quite basic and is currently limited to:

  • evaluating JS code
  • calling a JS function in the global scope
  • marshalling Aeson Values to and from JSValues.


Evaluate an expression:

import Quickjs

one_plus_two = quickjs $ do
  res <- eval "1+2"
  liftIO $ print res

Declare a function and call it on an argument:

call_f = quickjs $ do
  _ <- eval_ "f = (x) => x+1"
  res <- eval "f(2)"
  liftIO $ print res

Pass a Haskell value (which has a ToJSON instance) to the JS runtime:

aeson_marshall = quickjs $ do
  _ <- eval_ "f = (x) => x+1"
  res <- withJSValue (3::Int) $ \x -> call "f" [x]
  liftIO $ print res


Please feel free to report bugs/submit feature requests via the github issue tracker and submit any pull requests to the git repository