isLength function

bool isLength(
  1. String str,
  2. int min, [
  3. int? max
])

Returns true if the display-length of str is within `min`, `max`, counting surrogate pairs as single characters.

Implementation

bool isLength(String str, int min, [int? max]) {
  final pairs = surrogatePairsReg.allMatches(str).length;
  final len = str.length - pairs;
  return len >= min && (max == null || len <= max);
}