lib/dev.js
function setupSymlinks (module, modulesDir, callback) {

    let details = module.split('/');
    let modulePath = resolve(NODE_MODULES, details[1]);
    let devModulePath = resolve(modulesDir, module);

    rimraf(modulePath, err => {

        if (err) {
            return callback(err);
        }

        fs.symlink(devModulePath, modulePath, err => {

            if (err) {
                return callback(err);
            }

            callback();
        });
    });
}
function setupSymlinks (module, modulesDir, callback) {

    let details = module.split('/');
    let modulePath = resolve(NODE_MODULES, details[1]);
    let devModulePath = resolve(modulesDir, module);

    rimraf(modulePath, err => {

        if (err) {
            return callback(err);
        }

        fs.symlink(devModulePath, modulePath, err => {

            if (err) {
                return callback(err);
            }

            callback();
        });
    });
}
function setupSymlinks ( module , modulesDir , callback ) { let details = module . split ( '/' ) ; let modulePath = resolve ( NODE_MODULES , details [ 1 ] ) ; let devModulePath = resolve ( modulesDir , module ) ; rimraf ( modulePath , err => { if ( err ) { return callback ( err ) ; } fs . symlink ( devModulePath , modulePath , err => { if ( err ) { return callback ( err ) ; } callback ( ) ; } ) ; } ) ; }
this will remove the module from the registry and create all the required links
this will remove the module from the registry and create all the required links