GridWorld.fromString constructor

GridWorld.fromString(String x)

fromString initializes a world from a multi-line string.

The string argument should be a multi-line string like

'''
...#...
..#.#..
.#.#.#.
...#...
...#...
...#...
'''

The shape must be rectangular (not necessarily square).

Cells are initialized per the rules

• '.': dead
• anything else: alive

Implementation

factory GridWorld.fromString(String x) {
  final rawLines = x.split('\n');
  final lines = List<List<int>>.empty(growable: true);
  for (final line in rawLines) {
    if (line.isNotEmpty) {
      lines.add(line.codeUnits);
    }
  }
  if (lines.length < 2) {
    throw ArgumentError('must supply at least two lines');
  }
  final nR = lines.length;
  final nC = lines[0].length;
  for (var i = 1; i < lines.length; i++) {
    if (lines[i].length != nC) {
      throw ArgumentError('length (${lines[i].length}) of line $i must '
          'match length ($nC) of first line');
    }
  }
  final list = List<bool>.filled(nR * nC, false);
//    final list = <bool>[].filled(nR * nC,0);
  var k = 0;
  for (final line in lines) {
    for (final ch in line) {
      list[k] = ch != GridWorld.chDead;
      k++;
    }
  }
  return GridWorld(nR, list);
}