Sfshaza

// Starting "Hello World" app for the
// Getting Started with Flutter codelab.

import 'package:flutter/material.dart';

void main() => runApp(new MyApp());

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {

Sfshaza

String scream(int length) {
  return "A${'a' * length}h!";
}

main() {
  var values = [1, 2, 3, 5, 10, 50];
  values.skip(1).take(3).map(scream).forEach(print);
}

Sfshaza

String scream(int length) {
  return "A${'a' * length}h!";
}

main() {
  var values = [1, 2, 3, 5, 10, 50];
  values.map(scream).forEach(print);
}

Sfshaza

String scream(int length) {
  return "A${'a' * length}h!";
}

main() {
  var values = [1, 2, 3, 5, 10, 50];
  for (var length in values) {
    print(scream(length));
  }
}

Sfshaza

import 'dart:math';

abstract class Shape {
  factory Shape(String type) {
    if (type == "circle") return new Circle(2);
    if (type == "square") return new Square(2);
    throw new ArgumentError("Can't create $type.");
  }
  num get area;
}

Sfshaza

import 'dart:math';

abstract class Shape {
  factory Shape(String type) {
    if (type == 'circle') return new Circle(2);
    if (type == 'square') return new Square(2);
    throw 'Can\'t create $type.';
  }
  num get area;
}

Sfshaza

import 'dart:math';

abstract class Shape {
  num get area;
}

class Circle implements Shape {
  final num radius;
  Circle(this.radius);
  num get area => PI * pow(radius, 2);

Sfshaza

import 'dart:math';

abstract class Shape {
  factory Shape(String type) {
    if (type == 'circle') return new Circle(2);
    if (type == 'square') return new Square(2);
    // To trigger exception, don't implement a check for 'triangle'.
    throw 'Can\'t create $type.';
  }
  num get area;

Sfshaza

import 'dart:math';

abstract class Shape {
  num get area;
}

class Circle implements Shape {
  final num radius;
  Circle(this.radius);
  num get area => PI * pow(radius, 2);

Sfshaza

import 'dart:math';

class Rectangle {
  Point origin;
  int width;
  int height;

  Rectangle({this.origin = const Point(0, 0), this.width = 0, this.height = 0});
  
  @override