dart short style method

test.dart

void main() {
  print(f0()); // -> sss
  print(f1()); // -> null
  print(f2()); // -> sss
  print(f3()); // -> yyy

  var len = "dasada".split("").where((c) => c == 'a').length;
  print("LEN:$len"); //-> 3
}

String f0(){ return "sss"; }
String f1(){ "sss"; }

String f2() => "sss";
String f3() => false? "sss" : "yyy";

//String f4() =>{return "sss"}; //syntax error