small, recursive function to detect if item is member of a collection

member.js

function car(list){
  return list[0];
}

function cdr(list){
  return list.slice(1);
}

function memberp(a, list){
  if (!list.length) {
    return false;
  } else if ((car(list) == a) || (memberp(a, cdr(list)))) return true;
}

module.exports = memberp;