function hashToClassName (c) {
  let str = ''
  for (let prop in c) {
    if (c[prop]) {
      if (str) str += ' '
      str += prop
    }
  }
  return str
}
/** Convert a hashmap of CSS classes to a space-delimited className string
 *    @private
 */
Convert a hashmap of CSS classes to a space-delimited className string
@private
Convert a hashmap of CSS classes to a space - delimited className string @private
function hashToClassName (c) {
  let str = ''
  for (let prop in c) {
    if (c[prop]) {
      if (str) str += ' '
      str += prop
    }
  }
  return str
}
function hashToClassName ( c ) { let str = '' for ( let prop in c ) { if ( c [ prop ] ) { if ( str ) str += ' ' str += prop } } return str }
Convert a hashmap of CSS classes to a space-delimited className string
    @private
Convert a hashmap of CSS classes to a space - delimited className string @private