description

# replaceFirstMapped abstract method

String replaceFirstMapped(

1. Pattern from,
2. String replace(
   1. Match match
   ), [
3. int startIndex = 0

])

Replace the first occurrence of `from` in this string.

    const string = 'Dart is fun';
    print(string.replaceFirstMapped(
        'fun', (m) => 'open source')); // Dart is open source

    print(string.replaceFirstMapped(
        RegExp(r'\w(\w*)'), (m) => '<${m[0]}-${m[1]}>')); // <Dart-art> is fun

Returns a new string, which is this string except that the first match of `from`, starting from `startIndex`, is replaced by the result of calling `replace` with the match object.

The `startIndex` must be non-negative and no greater than length.

## Implementation

    String replaceFirstMapped(
      Pattern from,
      String replace(Match match), [
      int startIndex = 0,
    ]);