Attempt to handle errors in JS

app.js

// specifically creates a closure to handle specific error class with a given error handler
// it rethrows all other errors
const specifically = (errorClass) => (errHandler) => (err) => {
  if (err instanceof errorClass) {
    return errHandler(err)
  }

  throw err
}

// example usage

class ArgumentError extends Error {}
class SystemError extends Error {}
class UnhandledError extends Error {}

const argErrorHandler = (err) => {
  console.log('handled ArgumentError: ', err.message)
}
const systemErrorHandler = (err) => {
  console.log('handled SystemError: ', err.message)
}

const testFunc = async (errorClass, message) => {
  throw new errorClass(message)
}

// this is handled
testFunc(ArgumentError, 'bad argument').
  catch(specifically(SystemError)(systemErrorHandler)).
  catch(specifically(ArgumentError)(argErrorHandler))

// this is handled
testFunc(SystemError, 'system failure').
  catch(specifically(SystemError)(systemErrorHandler)).
  catch(specifically(ArgumentError)(argErrorHandler))

// this is not handled
testFunc(UnhandledError, 'BOOM!').
  catch(specifically(SystemError)(systemErrorHandler)).
  catch(specifically(ArgumentError)(argErrorHandler))

Todo: improve DSL with a “.with()”