How does pattern matching, introduced through Dart's more modern switch expressions and destructuring, let you write more concise and expressive code when handling different possible shapes of data?

Modern Dart versions introduced significantly more powerful pattern matching capabilities, including switch expressions that can directly return a value based on which specific pattern matches, along with destructuring, meaning extracting individual specific values directly out of a list, map, or object in a single concise step, and together these features let you write noticeably more concise, readable code when handling data that could take on several distinct possible different shapes, replacing what would otherwise require considerably more verbose conditional logic using traditional if else chains.

String describe(Object value) => switch (value) {
  int n when n > 0 => 'positive number',
  String s => 'a string: $s',
  _ => 'something else',
};