Strings

import 'package:characters/characters.dart'; //use characters library

void main() {

  //There is no Character type
  var char = 'a'; // String

  //String type immutable
  var txt0 = "I'm text.\n"; // String literal can use ""
  var txt1 = 'I\'m text'; // or '' (Dart way)
  print(txt1);
  print(txt1.length);
  print(txt1.codeUnits); // collections of UTF-16 code units
  print(txt1.runes); // Unicode code points - runes
  print(txt1.characters.length); // Unicode grapheme clusters, use characters library

  //Unicode
  print('I \u2764 Dart\u0021'); // hex code for the heart emoji and '!'
  print('I love \u{1F3AF}'); // use {} after FFFF value

  //Concatenation
  txt1 += '!';
  print('[' + txt1 + ']');

  //Interpolation
  print('Hi, $txt1');

  //StringBuffer
  final txt2 = StringBuffer();
  txt2.write('Hello, ');
  txt2.write('Dart!');
  print(txt2.toString());

  //Multi-line (''' or """)
  const txt3 = '''
- line 1
- line 2
- line 3''';
  print(txt3);

  //raw string (r' ' or r" ")
  print(r'C:\temp');

  //Methods
  var str = 'Dart is cool!'.toLowerCase();
  str = str.toUpperCase();
  print(str);
  print(str.contains('IS'));
  print(str.replaceAll('IS', 'IS REALLY'));

}