index.js
function store(obj, elem, key)
{
  Array.isArray(obj) ? obj.push(elem) : (obj[key] = elem);
}
function store(obj, elem, key)
{
  Array.isArray(obj) ? obj.push(elem) : (obj[key] = elem);
}
function store ( obj , elem , key ) { Array . isArray ( obj ) ? obj . push ( elem ) : ( obj [ key ] = elem ) ; }
Stores provided element in the provided object or array

@param   {object|array} obj - object or array to add to
@param   {mixed} elem - element to add
@param   {string|number} key - object's property key to add to
@returns {void}
Stores provided element in the provided object or array