My implementation of className, to allow more fluent class-binding in React

classname.js

export const classBinding = obj => {
  let classString = "";
  if (Array.isArray(obj)) {
    classString += obj.reduce((carry, item) => {
      if ((typeof item === "string" || typeof item === "number") && item)
        return `${carry}${carry ? " " : ""}${item}`;
      else if (item) return `${carry}${carry ? " " : ""}${classBinding(item)}`;
      else return carry + "";
    }, "");
  } else {
    if (obj) {
      if (typeof obj === "object") {
        classString += Object.entries(obj)
          .filter(entry => entry[1])
          .reduce(
            (carry, current) => carry + `${carry ? " " : ""}${current[0]}`,
            ""
          );
      } else if (typeof obj === "string") {
        classString += obj;
      } else classString += "";
    } else {
      classString += "";
    }
  }
  return classString.trim();
};

export const classNames = (...args) => classBinding(args);

// classNames('test', 'name') => 'test name'
// classNames({test: true, name: false, new: true}) => 'test new'
// classNames(['test', 'name']) => 'test name'
// classNames('test', {name: true}, ['jinx', {clean: true}], undefined, null) => 'test name jinx clean'