commonPrefix method

@useResult String commonPrefix()

Returns the longest common prefix of all strings in this list.

Returns empty string if list is empty or any element is empty.

Example:

['flower', 'flow', 'flight'].commonPrefix();  // 'fl'
['a', 'b'].commonPrefix();  // ''

Implementation

@useResult
String commonPrefix() {
  if (isEmpty) return '';
  String prefix = this[0];
  for (int i = 1; i < length; i++) {
    final String s = this[i];
    final int maxLen = prefix.length < s.length ? prefix.length : s.length;
    int j = 0;
    while (j < maxLen && prefix[j] == s[j]) {
      j++;
    }
    prefix = prefix.replaceRange(j, prefix.length, '');
    if (prefix.isEmpty) return '';
  }
  return prefix;
}