index.js

const { Future, IO } = require('ramda-fantasy');
const join2 = curryN(2, require('path').join);
const npa = require('npm-package-arg');

const ALIAS  = /:([^!]+)/;
const EXTEND = /!$/;
const parseAlias = pipe(
  S.match(ALIAS), chain(nth(1)));
const parseExtend = pipe(
  S.match(EXTEND), map(T));
const rm = replace(__, '');
const cleanArg = pipe(...map(rm, [ EXTEND, ALIAS ]));
const orEmpty = S.fromMaybe({});

const parseArg = (arg) => {
  const cleaned = cleanArg(arg);
  const { raw } = npa(cleaned);
  return mergeAll([
    orEmpty(map(createMapEntry('alias'),  parseAlias(arg))),
    orEmpty(map(createMapEntry('extend'), parseExtend(arg))),
    { raw }
  ]);
};

const parseArgv = (process) =>
  minimist(process.argv.slice(2), {
    alias: { h: 'help' }
  });

const main = (process) => {
  const processIO = IO.of(process);
  const env = map(prop('env'), processIO);
  const home = map(prop('home'), env);
  const replemPath = map(join2(__, '.replem'), home);
  const replemModules = map(join2(__, 'node_modules'), replemPath);
  const rrequire = IO.of(compose(require, join2)).ap(replemModules);
  const argv = map(parseArgv, processIO);
  const parsedArgs = map(pipe(prop('_'), map(parseArg)), argv);
}