insertLength function

String insertLength(
  1. String str, [
  2. dynamic len = 4,
  3. dynamic separator = ' '
])

Implementation

String insertLength(String str, [len = 4, separator = ' ']) {
  if (str.isEmpty) return str;
  return str.replaceAllMapped(RegExp('.{$len}'), (match) => '${match.group(0)}$separator');
}