>>> DO use ; instead of {} for empty constructor bodies
class Point {
  int x, y;
  Point(this.x, this.y) {}
}
<<<
class Point {
  int x, y;
  Point(this.x, this.y);
}
>>> DO indent block bodies two spaces.
hi() {
if (condition) { print('hi'); }
}
<<<
hi() {
  if (condition) {
    print('hi');
  }
}
>>> DON'T indent lines that are continued with a function expression.
var callback = new Future.delayed(const Duration(seconds: 1), () {
      print('I am a callback');
    });
<<<
var callback = new Future.delayed(const Duration(seconds: 1), () {
  print('I am a callback');
});
>>> DO place the opening curly brace ({) on the same line as what it follows.
class Foo {
  method() 
  {
    if (true) 
    {
      print('true');
    } else {
      print('false');
    }
  }
}
<<<
class Foo {
  method() {
    if (true) {
      print('true');
    } else {
      print('false');
    }
  }
}
>>> DO use curly braces for all flow control structures.
flow() {
  if (true) print('sanity');
  else
    print('opposite day!');
}
<<<
flow() {
  if (true) {
    print('sanity');
  } else {
    print('opposite day!');
  }
}
>>> ... short if statements with no else may omit the braces ...
except() {
  if (arg == null) return defaultValue;
}
<<<
except() {
  if (arg == null) return defaultValue;
}
>>> DO indent switch cases two spaces and case bodies four spaces
switches() {
  switch (fruit) {
    case 'apple':
    print('delish');
    break;

    case 'durian':
    print('stinky');
    break;
  }
}
<<<
switches() {
  switch (fruit) {
    case 'apple':
      print('delish');
      break;

    case 'durian':
      print('stinky');
      break;
  }
}
>>> DO use spaces around binary and ternary operators, etc...
spaces() {
  a=1+2/(3* - b);
  c= ! condition==a>b;
  d= condition?b:object.method(a,b,c);
  if (obj is !SomeType) print('not SomeType');
}
<<<
spaces() {
  a = 1 + 2 / (3 * -b);
  c = !condition == a > b;
  d = condition ? b : object.method(a, b, c);
  if (obj is! SomeType) print('not SomeType');
}
>>> DO place spaces around in, and after each ; in a loop.
loop() {
  for (var i = 0;i<100;i++) {
    print(i);
  }
  for (final item in  collection) {
    print(item);
  }
}
<<<
loop() {
  for (var i = 0; i < 100; i++) {
    print(i);
  }
  for (final item in collection) {
    print(item);
  }
}
>>> DO use a space after flow-control keywords.
flow() {
  while(foo) {
    print(foo);
  }

  try{
    flow();
  }catch(e) {
    print(e);
  }
}
<<<
flow() {
  while (foo) {
    print(foo);
  }

  try {
    flow();
  } catch (e) {
    print(e);
  }
}
>>> DON'T use a space after (, [, and {, or before ), ], and }.
spaces() {
  var numbers = <int> [ 1, 2,( 3+4 ) ];
}
<<<
spaces() {
  var numbers = <int>[1, 2, (3 + 4)];
}
>>> DO use a space before { in function and method bodies.
getEmptyFn(a){
  return (){};
}
<<<
getEmptyFn(a) {
  return () {};
}
>>> DO format constructor initialization lists with each field on its own line.
class MyClass {
  var firstField, secondField, thirdField;
  MyClass() : firstField = "some value", secondField = "another",
        thirdField = "last";
}
<<<
class MyClass {
  var firstField, secondField, thirdField;
  MyClass()
      : firstField = "some value",
        secondField = "another",
        thirdField = "last";
}
>>> DO use a space after : in named parameters and named arguments.
class ListBox {
  bool showScrollbars;

  ListBox({this.showScrollbars: false});
}

main() {
  new ListBox(showScrollbars:true);
  new ListBox(showScrollbars : true);
}
<<<
class ListBox {
  bool showScrollbars;

  ListBox({this.showScrollbars: false});
}

main() {
  new ListBox(showScrollbars: true);
  new ListBox(showScrollbars: true);
}
>>> DO use a spaces around = in optional positional parameters.
class HttpServer {
  static Future<HttpServer> listen([int port=80]) {
    print('hi!');
  }
}
<<<
class HttpServer {
  static Future<HttpServer> listen([int port = 80]) {
    print('hi!');
  }
}
>>> DO use four spaces for method cascades
var list = new List()
  ..addAll([1, 2, 3])
  ..addAll([4, 5, 6]);
<<<
var list = new List()
    ..addAll([1, 2, 3])
    ..addAll([4, 5, 6]);