[ { "path": "chapter1/abstract_factory.py", "content": "class Frog:\n\n def __init__(self, name):\n self.name = name\n\n def __str__(self):\n return self.name\n\n def interact_with(self, obstacle):\n print('{} the Frog encounters {} and {}!'.format(self,\n obstacle, obstacle.action()))\n\n\nclass Bug:\n\n def __str__(self):\n return 'a bug'\n\n def action(self):\n return 'eats it'\n\n\nclass FrogWorld:\n\n def __init__(self, name):\n print(self)\n self.player_name = name\n\n def __str__(self):\n return '\\n\\n\\t------ Frog World ———'\n\n def make_character(self):\n return Frog(self.player_name)\n\n def make_obstacle(self):\n return Bug()\n\n\nclass Wizard:\n\n def __init__(self, name):\n self.name = name\n\n def __str__(self):\n return self.name\n\n def interact_with(self, obstacle):\n print('{} the Wizard battles against {} and {}!'.format(self, obstacle, obstacle.action()))\n\n\nclass Ork:\n\n def __str__(self):\n return 'an evil ork'\n\n def action(self):\n return 'kills it'\n\n\nclass WizardWorld:\n\n def __init__(self, name):\n print(self)\n self.player_name = name\n\n def __str__(self):\n return '\\n\\n\\t------ Wizard World ———'\n\n def make_character(self):\n return Wizard(self.player_name)\n\n def make_obstacle(self):\n return Ork()\n\n\nclass GameEnvironment:\n\n def __init__(self, factory):\n self.hero = factory.make_character()\n self.obstacle = factory.make_obstacle()\n\n def play(self):\n self.hero.interact_with(self.obstacle)\n\n\ndef validate_age(name):\n try:\n age = input('Welcome {}. How old are you? '.format(name))\n age = int(age)\n except ValueError as err:\n print(\"Age {} is invalid, please try \\\n again…\".format(age))\n return (False, age)\n return (True, age)\n\n\ndef main():\n name = input(\"Hello. What's your name? \")\n valid_input = False\n while not valid_input:\n valid_input, age = validate_age(name)\n game = FrogWorld if age < 18 else WizardWorld\n environment = GameEnvironment(game(name))\n environment.play()\n\nif __name__ == '__main__':\n main()\n" }, { "path": "chapter1/data/donut.json", "content": "[\n {\n \"id\": \"0001\",\n \"type\": \"donut\",\n \"name\": \"Cake\",\n \"ppu\": 0.55,\n \"batters\": {\n \"batter\": [\n {\n \"id\": \"1001\",\n \"type\": \"Regular\"\n },\n {\n \"id\": \"1002\",\n \"type\": \"Chocolate\"\n },\n {\n \"id\": \"1003\",\n \"type\": \"Blueberry\"\n },\n {\n \"id\": \"1004\",\n \"type\": \"Devil's Food\"\n }\n ]\n },\n \"topping\": [\n {\n \"id\": \"5001\",\n \"type\": \"None\"\n },\n {\n \"id\": \"5002\",\n \"type\": \"Glazed\"\n },\n {\n \"id\": \"5005\",\n \"type\": \"Sugar\"\n },\n {\n \"id\": \"5007\",\n \"type\": \"Powdered Sugar\"\n },\n {\n \"id\": \"5006\",\n \"type\": \"Chocolate with Sprinkles\"\n },\n {\n \"id\": \"5003\",\n \"type\": \"Chocolate\"\n },\n {\n \"id\": \"5004\",\n \"type\": \"Maple\"\n }\n ]\n },\n {\n \"id\": \"0002\",\n \"type\": \"donut\",\n \"name\": \"Raised\",\n \"ppu\": 0.55,\n \"batters\": {\n \"batter\": [\n {\n \"id\": \"1001\",\n \"type\": \"Regular\"\n }\n ]\n },\n \"topping\": [\n {\n \"id\": \"5001\",\n \"type\": \"None\"\n },\n {\n \"id\": \"5002\",\n \"type\": \"Glazed\"\n },\n {\n \"id\": \"5005\",\n \"type\": \"Sugar\"\n },\n {\n \"id\": \"5003\",\n \"type\": \"Chocolate\"\n },\n {\n \"id\": \"5004\",\n \"type\": \"Maple\"\n }\n ]\n },\n {\n \"id\": \"0003\",\n \"type\": \"donut\",\n \"name\": \"Old Fashioned\",\n \"ppu\": 0.55,\n \"batters\": {\n \"batter\": [\n {\n \"id\": \"1001\",\n \"type\": \"Regular\"\n },\n {\n \"id\": \"1002\",\n \"type\": \"Chocolate\"\n }\n ]\n },\n \"topping\": [\n {\n \"id\": \"5001\",\n \"type\": \"None\"\n },\n {\n \"id\": \"5002\",\n \"type\": \"Glazed\"\n },\n {\n \"id\": \"5003\",\n \"type\": \"Chocolate\"\n },\n {\n \"id\": \"5004\",\n \"type\": \"Maple\"\n }\n ]\n }\n]" }, { "path": "chapter1/data/person.xml", "content": "\n \n John\n Smith\n 25\n
\n 21 2nd Street\n New York\n NY\n 10021\n
\n \n 212 555-1234\n 646 555-4567\n \n \n male\n \n \n \n Jimy\n Liar\n 19\n
\n 18 2nd Street\n New York\n NY\n 10021\n
\n \n 212 555-1234\n \n \n male\n \n \n \n Patty\n Liar\n 20\n
\n 18 2nd Street\n New York\n NY\n 10021\n
\n \n 212 555-1234\n 001 452-8819\n \n \n female\n \n \n" }, { "path": "chapter1/factory_method.py", "content": "import xml.etree.ElementTree as etree\nimport json\n\n\nclass JSONConnector:\n\n def __init__(self, filepath):\n self.data = dict()\n with open(filepath, mode='r', encoding='utf-8') as f:\n self.data = json.load(f)\n\n @property\n def parsed_data(self):\n return self.data\n\n\nclass XMLConnector:\n\n def __init__(self, filepath):\n self.tree = etree.parse(filepath)\n\n @property\n def parsed_data(self):\n return self.tree\n\n\ndef connection_factory(filepath):\n if filepath.endswith('json'):\n connector = JSONConnector\n elif filepath.endswith('xml'):\n connector = XMLConnector\n else:\n raise ValueError('Cannot connect to {}'.format(filepath))\n return connector(filepath)\n\n\ndef connect_to(filepath):\n factory = None\n try:\n factory = connection_factory(filepath)\n except ValueError as ve:\n print(ve)\n return factory\n\n\ndef main():\n sqlite_factory = connect_to('data/person.sq3')\n print()\n\n xml_factory = connect_to('data/person.xml')\n xml_data = xml_factory.parsed_data\n liars = xml_data.findall(\".//{}[{}='{}']\".format('person',\n 'lastName', 'Liar'))\n print('found: {} persons'.format(len(liars)))\n for liar in liars:\n print('first name: {}'.format(liar.find('firstName').text))\n print('last name: {}'.format(liar.find('lastName').text))\n [print('phone number ({})'.format(p.attrib['type']),\n p.text) for p in liar.find('phoneNumbers')]\n\n print()\n\n json_factory = connect_to('data/donut.json')\n json_data = json_factory.parsed_data\n print('found: {} donuts'.format(len(json_data)))\n for donut in json_data:\n print('name: {}'.format(donut['name']))\n print('price: ${}'.format(donut['ppu']))\n [print('topping: {} {}'.format(t['id'], t['type'])) for t in donut['topping']]\n\nif __name__ == '__main__':\n main()\n" }, { "path": "chapter1/id.py", "content": "class A(object):\n pass\n\nif __name__ == '__main__':\n a = A()\n b = A()\n\n print(id(a) == id(b))\n print(a, b)\n" }, { "path": "chapter10/chain.py", "content": "class Event:\n\n def __init__(self, name):\n self.name = name\n\n def __str__(self):\n return self.name\n\n\nclass Widget:\n\n def __init__(self, parent=None):\n self.parent = parent\n\n def handle(self, event):\n handler = 'handle_{}'.format(event)\n if hasattr(self, handler):\n method = getattr(self, handler)\n method(event)\n elif self.parent:\n self.parent.handle(event)\n elif hasattr(self, 'handle_default'):\n self.handle_default(event)\n\n\nclass MainWindow(Widget):\n\n def handle_close(self, event):\n print('MainWindow: {}'.format(event))\n\n def handle_default(self, event):\n print('MainWindow Default: {}'.format(event))\n\n\nclass SendDialog(Widget):\n\n def handle_paint(self, event):\n print('SendDialog: {}'.format(event))\n\n\nclass MsgText(Widget):\n\n def handle_down(self, event):\n print('MsgText: {}'.format(event))\n\n\ndef main():\n mw = MainWindow()\n sd = SendDialog(mw)\n msg = MsgText(sd)\n\n for e in ('down', 'paint', 'unhandled', 'close'):\n evt = Event(e)\n print('\\nSending event -{}- to MainWindow'.format(evt))\n mw.handle(evt)\n print('Sending event -{}- to SendDialog'.format(evt))\n sd.handle(evt)\n print('Sending event -{}- to MsgText'.format(evt))\n msg.handle(evt)\n\nif __name__ == '__main__':\n main()\n" }, { "path": "chapter11/command.py", "content": "import os\n\nverbose = True\n\n\nclass RenameFile:\n\n def __init__(self, path_src, path_dest):\n self.src, self.dest = path_src, path_dest\n\n def execute(self):\n if verbose:\n print(\"[renaming '{}' to '{}']\".format(self.src, self.dest))\n os.rename(self.src, self.dest)\n\n def undo(self):\n if verbose:\n print(\"[renaming '{}' back to '{}']\".format(self.dest, self.src))\n os.rename(self.dest, self.src)\n\n\nclass CreateFile:\n\n def __init__(self, path, txt='hello world\\n'):\n self.path, self.txt = path, txt\n\n def execute(self):\n if verbose:\n print(\"[creating file '{}']\".format(self.path))\n with open(self.path, mode='w', encoding='utf-8') as out_file:\n out_file.write(self.txt)\n\n def undo(self):\n delete_file(self.path)\n\n\nclass ReadFile:\n\n def __init__(self, path):\n self.path = path\n\n def execute(self):\n if verbose:\n print(\"[reading file '{}']\".format(self.path))\n with open(self.path, mode='r', encoding='utf-8') as in_file:\n print(in_file.read(), end='')\n\n\ndef delete_file(path):\n if verbose:\n print(\"deleting file '{}'\".format(path))\n os.remove(path)\n\n\ndef main():\n orig_name, new_name = 'file1', 'file2'\n\n commands = []\n for cmd in CreateFile(orig_name), ReadFile(orig_name), RenameFile(orig_name, new_name):\n commands.append(cmd)\n\n [c.execute() for c in commands]\n\n answer = input('reverse the executed commands? [y/n] ')\n\n if answer not in 'yY':\n print(\"the result is {}\".format(new_name))\n exit()\n\n for c in reversed(commands):\n try:\n c.undo()\n except AttributeError as e:\n pass\n\nif __name__ == '__main__':\n main()\n" }, { "path": "chapter11/first-class.py", "content": "import os\n\nverbose = True\n\n\nclass RenameFile:\n\n def __init__(self, path_src, path_dest):\n self.src, self.dest = path_src, path_dest\n\n def execute(self):\n if verbose:\n print(\"[renaming '{}' to '{}']\".format(self.src, self.dest))\n os.rename(self.src, self.dest)\n\n def undo(self):\n if verbose:\n print(\"[renaming '{}' back to '{}']\".format(self.dest, self.src))\n os.rename(self.dest, self.src)\n\n\nclass CreateFile:\n\n def __init__(self, path, txt='hello world\\n'):\n self.path, self.txt = path, txt\n\n def execute(self):\n if verbose:\n print(\"[creating file '{}']\".format(self.path))\n with open(self.path, mode='w', encoding='utf-8') as out_file:\n out_file.write(self.txt)\n\n def undo(self):\n delete_file(self.path)\n\n\nclass ReadFile:\n\n def __init__(self, path):\n self.path = path\n\n def execute(self):\n if verbose:\n print(\"[reading file '{}']\".format(self.path))\n with open(self.path, mode='r', encoding='utf-8') as in_file:\n print(in_file.read(), end='')\n\n\ndef delete_file(path):\n if verbose:\n print(\"deleting file '{}'\".format(path))\n os.remove(path)\n\n\ndef main():\n orig_name = 'file1'\n df = delete_file\n\n commands = []\n commands.append(df)\n\n for c in commands:\n try:\n c.execute()\n except AttributeError as e:\n df(orig_name)\n\n for c in reversed(commands):\n try:\n c.undo()\n except AttributeError as e:\n pass\n\nif __name__ == '__main__':\n '''\n 译注：这个程序会异常退出\n '''\n main()\n" }, { "path": "chapter12/interpreter.py", "content": "# coding: utf-8\n\nfrom pyparsing import Word, OneOrMore, Optional, Group, Suppress, alphanums\n\n\nclass Gate:\n\n def __init__(self):\n self.is_open = False\n\n def __str__(self):\n return 'open' if self.is_open else 'closed'\n\n def open(self):\n print('opening the gate')\n self.is_open = True\n\n def close(self):\n print('closing the gate')\n self.is_open = False\n\n\nclass Garage:\n\n def __init__(self):\n self.is_open = False\n\n def __str__(self):\n return 'open' if self.is_open else 'closed'\n\n def open(self):\n print('opening the garage')\n self.is_open = True\n\n def close(self):\n print('closing the garage')\n self.is_open = False\n\n\nclass Aircondition:\n\n def __init__(self):\n self.is_on = False\n\n def __str__(self):\n return 'on' if self.is_on else 'off'\n\n def turn_on(self):\n print('turning on the aircondition')\n self.is_on = True\n\n def turn_off(self):\n print('turning off the aircondition')\n self.is_on = False\n\n\nclass Heating:\n\n def __init__(self):\n self.is_on = False\n\n def __str__(self):\n return 'on' if self.is_on else 'off'\n\n def turn_on(self):\n print('turning on the heating')\n self.is_on = True\n\n def turn_off(self):\n print('turning off the heating')\n self.is_on = False\n\n\nclass Boiler:\n\n def __init__(self):\n self.temperature = 83 # in celsius\n\n def __str__(self):\n return 'boiler temperature: {}'.format(self.temperature)\n\n def increase_temperature(self, amount):\n print(\"increasing the boiler's temperature by {} degrees\".format(amount))\n self.temperature += amount\n\n def decrease_temperature(self, amount):\n print(\"decreasing the boiler's temperature by {} degrees\".format(amount))\n self.temperature -= amount\n\n\nclass Fridge:\n\n def __init__(self):\n self.temperature = 2 # 单位为摄氏度\n\n def __str__(self):\n return 'fridge temperature: {}'.format(self.temperature)\n\n def increase_temperature(self, amount):\n print(\"increasing the fridge's temperature by {} degrees\".format(amount))\n self.temperature += amount\n\n def decrease_temperature(self, amount):\n print(\"decreasing the fridge's temperature by {} degrees\".format(amount))\n self.temperature -= amount\n\n\ndef main():\n word = Word(alphanums)\n command = Group(OneOrMore(word))\n token = Suppress(\"->\")\n device = Group(OneOrMore(word))\n argument = Group(OneOrMore(word))\n event = command + token + device + Optional(token + argument)\n\n gate = Gate()\n garage = Garage()\n airco = Aircondition()\n heating = Heating()\n boiler = Boiler()\n fridge = Fridge()\n\n tests = ('open -> gate',\n 'close -> garage',\n 'turn on -> aircondition',\n 'turn off -> heating',\n 'increase -> boiler temperature -> 5 degrees',\n 'decrease -> fridge temperature -> 2 degrees')\n open_actions = {'gate': gate.open,\n 'garage': garage.open,\n 'aircondition': airco.turn_on,\n 'heating': heating.turn_on,\n 'boiler temperature': boiler.increase_temperature,\n 'fridge temperature': fridge.increase_temperature}\n close_actions = {'gate': gate.close,\n 'garage': garage.close,\n 'aircondition': airco.turn_off,\n 'heating': heating.turn_off,\n 'boiler temperature': boiler.decrease_temperature,\n 'fridge temperature': fridge.decrease_temperature}\n\n for t in tests:\n if len(event.parseString(t)) == 2: # 没有参数\n cmd, dev = event.parseString(t)\n cmd_str, dev_str = ' '.join(cmd), ' '.join(dev)\n if 'open' in cmd_str or 'turn on' in cmd_str:\n open_actions[dev_str]()\n elif 'close' in cmd_str or 'turn off' in cmd_str:\n close_actions[dev_str]()\n elif len(event.parseString(t)) == 3: # 有参数\n cmd, dev, arg = event.parseString(t)\n cmd_str, dev_str, arg_str = ' '.join(cmd), ' '.join(dev), ' '.join(arg)\n num_arg = 0\n try:\n num_arg = int(arg_str.split()[0]) # 抽取数值部分\n except ValueError as err:\n print(\"expected number but got: '{}'\".format(arg_str[0]))\n if 'increase' in cmd_str and num_arg > 0:\n open_actions[dev_str](num_arg)\n elif 'decrease' in cmd_str and num_arg > 0:\n close_actions[dev_str](num_arg)\n\nif __name__ == '__main__':\n main()\n" }, { "path": "chapter13/observer.py", "content": "class Publisher:\n\n def __init__(self):\n self.observers = []\n\n def add(self, observer):\n if observer not in self.observers:\n self.observers.append(observer)\n else:\n print('Failed to add: {}'.format(observer))\n\n def remove(self, observer):\n try:\n self.observers.remove(observer)\n except ValueError:\n print('Failed to remove: {}'.format(observer))\n\n def notify(self):\n [o.notify(self) for o in self.observers]\n\n\nclass DefaultFormatter(Publisher):\n\n def __init__(self, name):\n Publisher.__init__(self)\n self.name = name\n self._data = 0\n\n def __str__(self):\n return \"{}: '{}' has data = {}\".format(type(self).__name__, self.name, self._data)\n\n @property\n def data(self):\n return self._data\n\n @data.setter\n def data(self, new_value):\n try:\n self._data = int(new_value)\n except ValueError as e:\n print('Error: {}'.format(e))\n else:\n self.notify()\n\n\nclass HexFormatter:\n\n def notify(self, publisher):\n print(\"{}: '{}' has now hex data = {}\".format(type(self).__name__,\n publisher.name, hex(publisher.data)))\n\n\nclass BinaryFormatter:\n\n def notify(self, publisher):\n print(\"{}: '{}' has now bin data = {}\".format(type(self).__name__,\n publisher.name, bin(publisher.data)))\n\n\ndef main():\n df = DefaultFormatter('test1')\n print(df)\n\n print()\n hf = HexFormatter()\n df.add(hf)\n df.data = 3\n print(df)\n\n print()\n bf = BinaryFormatter()\n df.add(bf)\n df.data = 21\n print(df)\n\n print()\n df.remove(hf)\n df.data = 40\n print(df)\n\n print()\n df.remove(hf)\n df.add(bf)\n df.data = 'hello'\n print(df)\n\n print()\n df.data = 15.8\n print(df)\n\nif __name__ == '__main__':\n main()\n" }, { "path": "chapter14/state.py", "content": "from state_machine import State, Event, acts_as_state_machine, after, before, InvalidStateTransition\n\n\n@acts_as_state_machine\nclass Process:\n created = State(initial=True)\n waiting = State()\n running = State()\n terminated = State()\n blocked = State()\n swapped_out_waiting = State()\n swapped_out_blocked = State()\n\n wait = Event(from_states=(created, running, blocked,\n swapped_out_waiting), to_state=waiting)\n run = Event(from_states=waiting, to_state=running)\n terminate = Event(from_states=running, to_state=terminated)\n block = Event(from_states=(running, swapped_out_blocked),\n to_state=blocked)\n swap_wait = Event(from_states=waiting, to_state=swapped_out_waiting)\n swap_block = Event(from_states=blocked, to_state=swapped_out_blocked)\n\n def __init__(self, name):\n self.name = name\n\n @after('wait')\n def wait_info(self):\n print('{} entered waiting mode'.format(self.name))\n\n @after('run')\n def run_info(self):\n print('{} is running'.format(self.name))\n\n @before('terminate')\n def terminate_info(self):\n print('{} terminated'.format(self.name))\n\n @after('block')\n def block_info(self):\n print('{} is blocked'.format(self.name))\n\n @after('swap_wait')\n def swap_wait_info(self):\n print('{} is swapped out and waiting'.format(self.name))\n\n @after('swap_block')\n def swap_block_info(self):\n print('{} is swapped out and blocked'.format(self.name))\n\n\ndef transition(process, event, event_name):\n try:\n event()\n except InvalidStateTransition as err:\n print('Error: transition of {} from {} to {} failed'.format(process.name,\n process.current_state, event_name))\n\n\ndef state_info(process):\n print('state of {}: {}'.format(process.name, process.current_state))\n\n\ndef main():\n RUNNING = 'running'\n WAITING = 'waiting'\n BLOCKED = 'blocked'\n TERMINATED = 'terminated'\n\n p1, p2 = Process('process1'), Process('process2')\n [state_info(p) for p in (p1, p2)]\n\n print()\n transition(p1, p1.wait, WAITING)\n transition(p2, p2.terminate, TERMINATED)\n [state_info(p) for p in (p1, p2)]\n\n print()\n transition(p1, p1.run, RUNNING)\n transition(p2, p2.wait, WAITING)\n [state_info(p) for p in (p1, p2)]\n\n print()\n transition(p2, p2.run, RUNNING)\n [state_info(p) for p in (p1, p2)]\n\n print()\n [transition(p, p.block, BLOCKED) for p in (p1, p2)]\n [state_info(p) for p in (p1, p2)]\n\n print()\n [transition(p, p.terminate, TERMINATED) for p in (p1, p2)]\n [state_info(p) for p in (p1, p2)]\n\nif __name__ == '__main__':\n main()\n" }, { "path": "chapter15/langs.py", "content": "import pprint\nfrom collections import namedtuple\nfrom operator import attrgetter\nif __name__ == '__main__':\n ProgrammingLang = namedtuple('ProgrammingLang', 'name ranking')\n stats = (('Ruby', 14), ('Javascript', 8), ('Python', 7),\n ('Scala', 31), ('Swift', 18), ('Lisp', 23))\n lang_stats = [ProgrammingLang(n, r) for n, r in stats]\n pp = pprint.PrettyPrinter(indent=5)\n pp.pprint(sorted(lang_stats, key=attrgetter('name')))\n print()\n pp.pprint(sorted(lang_stats, key=attrgetter('ranking')))\n" }, { "path": "chapter15/strategy.py", "content": "# coding: utf-8\n\nimport time\nSLOW = 3 # 单位为秒\nLIMIT = 5 # 字符数\nWARNING = 'too bad, you picked the slow algorithm :('\n\n\ndef pairs(seq):\n n = len(seq)\n for i in range(n):\n yield seq[i], seq[(i + 1) % n]\n\n\ndef allUniqueSort(s):\n if len(s) > LIMIT:\n print(WARNING)\n time.sleep(SLOW)\n srtStr = sorted(s)\n for (c1, c2) in pairs(srtStr):\n if c1 == c2:\n return False\n return True\n\n\ndef allUniqueSet(s):\n if len(s) < LIMIT:\n print(WARNING)\n time.sleep(SLOW)\n return True if len(set(s)) == len(s) else False\n\n\ndef allUnique(s, strategy):\n return strategy(s)\n\n\ndef main():\n while True:\n word = None\n while not word:\n word = input('Insert word (type quit to exit)> ')\n if word == 'quit':\n print('bye')\n return\n\n strategy_picked = None\n strategies = {'1': allUniqueSet, '2': allUniqueSort}\n while strategy_picked not in strategies.keys():\n strategy_picked = input('Choose strategy: [1] Use a set, [2] Sort and pair> ')\n\n try:\n strategy = strategies[strategy_picked]\n print('allUnique({}): {}'.format(word, allUnique(word, strategy)))\n except KeyError as err:\n print('Incorrect option: {}'.format(strategy_picked))\n\nif __name__ == '__main__':\n main()\n" }, { "path": "chapter16/graph.py", "content": "# coding: utf-8\n\n\ndef bfs(graph, start, end):\n path = []\n visited = [start]\n while visited:\n current = visited.pop(0)\n if current not in path:\n path.append(current)\n if current == end:\n print(path)\n return (True, path)\n # 两个顶点不相连，则跳过\n if current not in graph:\n continue\n visited = visited + graph[current]\n return (False, path)\n\n\ndef dfs(graph, start, end):\n path = []\n visited = [start]\n while visited:\n current = visited.pop(0)\n if current not in path:\n path.append(current)\n if current == end:\n print(path)\n return (True, path)\n # 两个顶点不相连，则跳过\n if current not in graph:\n continue\n visited = graph[current] + visited\n return (False, path)\n\n\ndef main():\n graph = {\n 'Frankfurt': ['Mannheim', 'Wurzburg', 'Kassel'],\n 'Mannheim': ['Karlsruhe'],\n 'Karlsruhe': ['Augsburg'],\n 'Augsburg': ['Munchen'],\n 'Wurzburg': ['Erfurt', 'Nurnberg'],\n 'Nurnberg': ['Stuttgart', 'Munchen'],\n 'Kassel': ['Munchen'],\n 'Erfurt': [],\n 'Stuttgart': [],\n 'Munchen': []\n }\n\n bfs_path = bfs(graph, 'Frankfurt', 'Nurnberg')\n dfs_path = dfs(graph, 'Frankfurt', 'Nurnberg')\n print('bfs Frankfurt-Nurnberg: {}'.format(bfs_path[1] if bfs_path[0] else 'Not found'))\n print('dfs Frankfurt-Nurnberg: {}'.format(dfs_path[1] if dfs_path[0] else 'Not found'))\n\n bfs_nopath = bfs(graph, 'Wurzburg', 'Kassel')\n print('bfs Wurzburg-Kassel: {}'.format(bfs_nopath[1] if bfs_nopath[0] else 'Not found'))\n dfs_nopath = dfs(graph, 'Wurzburg', 'Kassel')\n print('dfs Wurzburg-Kassel: {}'.format(dfs_nopath[1] if dfs_nopath[0] else 'Not found'))\n\nif __name__ == '__main__':\n main()\n" }, { "path": "chapter16/graph_template.py", "content": "# coding: utf-8\n\n\ndef traverse(graph, start, end, action):\n path = []\n visited = [start]\n while visited:\n current = visited.pop(0)\n if current not in path:\n path.append(current)\n if current == end:\n return (True, path)\n # 两个顶点不相连，则跳过\n if current not in graph:\n continue\n visited = action(visited, graph[current])\n return (False, path)\n\n\ndef extend_bfs_path(visited, current):\n return visited + current\n\n\ndef extend_dfs_path(visited, current):\n return current + visited\n\n\ndef main():\n graph = {\n 'Frankfurt': ['Mannheim', 'Wurzburg', 'Kassel'],\n 'Mannheim': ['Karlsruhe'],\n 'Karlsruhe': ['Augsburg'],\n 'Augsburg': ['Munchen'],\n 'Wurzburg': ['Erfurt', 'Nurnberg'],\n 'Nurnberg': ['Stuttgart', 'Munchen'],\n 'Kassel': ['Munchen'],\n 'Erfurt': [],\n 'Stuttgart': [],\n 'Munchen': []\n }\n\n bfs_path = traverse(graph, 'Frankfurt', 'Nurnberg', extend_bfs_path)\n dfs_path = traverse(graph, 'Frankfurt', 'Nurnberg', extend_dfs_path)\n print('bfs Frankfurt-Nurnberg: {}'.format(bfs_path[1] if bfs_path[0] else 'Not found'))\n print('dfs Frankfurt-Nurnberg: {}'.format(dfs_path[1] if dfs_path[0] else 'Not found'))\n\n bfs_nopath = traverse(graph, 'Wurzburg', 'Kassel', extend_bfs_path)\n print('bfs Wurzburg-Kassel: {}'.format(bfs_nopath[1] if bfs_nopath[0] else 'Not found'))\n dfs_nopath = traverse(graph, 'Wurzburg', 'Kassel', extend_dfs_path)\n print('dfs Wurzburg-Kassel: {}'.format(dfs_nopath[1] if dfs_nopath[0] else 'Not found'))\n\nif __name__ == '__main__':\n main()\n" }, { "path": "chapter16/graph_template_slower.py", "content": "# coding: utf-8\n\nBFS = 1\nDFS = 2\n\n\ndef traverse(graph, start, end, algorithm):\n path = []\n visited = [start]\n while visited:\n current = visited.pop(0)\n if current not in path:\n path.append(current)\n if current == end:\n return (True, path)\n # 顶点不相连，则跳过\n if current not in graph:\n continue\n if algorithm == BFS:\n visited = extend_bfs_path(visited, graph[current])\n elif algorithm == DFS:\n visited = extend_dfs_path(visited, graph[current])\n else:\n raise ValueError(\"No such algorithm\")\n return (False, path)\n\n\ndef extend_bfs_path(visited, current):\n return visited + current\n\n\ndef extend_dfs_path(visited, current):\n return current + visited\n\n\ndef main():\n graph = {\n 'Frankfurt': ['Mannheim', 'Wurzburg', 'Kassel'],\n 'Mannheim': ['Karlsruhe'],\n 'Karlsruhe': ['Augsburg'],\n 'Augsburg': ['Munchen'],\n 'Wurzburg': ['Erfurt', 'Nurnberg'],\n 'Nurnberg': ['Stuttgart', 'Munchen'],\n 'Kassel': ['Munchen'],\n 'Erfurt': [],\n 'Stuttgart': [],\n 'Munchen': []\n }\n\n bfs_path = traverse(graph, 'Frankfurt', 'Nurnberg', 1)\n dfs_path = traverse(graph, 'Frankfurt', 'Nurnberg', 2)\n print('bfs Frankfurt-Nurnberg: {}'.format(bfs_path[1] if bfs_path[0] else 'Not found'))\n print('dfs Frankfurt-Nurnberg: {}'.format(dfs_path[1] if dfs_path[0] else 'Not found'))\n\n bfs_nopath = traverse(graph, 'Wurzburg', 'Kassel', 1)\n print('bfs Wurzburg-Kassel: {}'.format(bfs_nopath[1] if bfs_nopath[0] else 'Not found'))\n dfs_nopath = traverse(graph, 'Wurzburg', 'Kassel', 2)\n print('dfs Wurzburg-Kassel: {}'.format(dfs_nopath[1] if dfs_nopath[0] else 'Not found'))\n\nif __name__ == '__main__':\n main()\n" }, { "path": "chapter16/template.py", "content": "from cowpy import cow\n\n\ndef dots_style(msg):\n msg = msg.capitalize()\n msg = '.' * 10 + msg + '.' * 10\n return msg\n\n\ndef admire_style(msg):\n msg = msg.upper()\n return '!'.join(msg)\n\n\ndef cow_style(msg):\n msg = cow.milk_random_cow(msg)\n return msg\n\n\ndef generate_banner(msg, style=dots_style):\n print('-- start of banner --')\n print(style(msg))\n print('-- end of banner --\\n\\n')\n\n\ndef main():\n msg = 'happy coding'\n [generate_banner(msg, style) for style in (dots_style, admire_style, cow_style)]\n\nif __name__ == '__main__':\n main()\n" }, { "path": "chapter2/apple-factory.py", "content": "# coding: utf-8\n\nMINI14 = '1.4GHz Mac mini'\n\n\nclass AppleFactory:\n\n class MacMini14:\n\n def __init__(self):\n self.memory = 4 # 单位为GB\n self.hdd = 500 # 单位为GB\n self.gpu = 'Intel HD Graphics 5000'\n\n def __str__(self):\n info = ('Model: {}'.format(MINI14),\n 'Memory: {}GB'.format(self.memory),\n 'Hard Disk: {}GB'.format(self.hdd),\n 'Graphics Card: {}'.format(self.gpu))\n return '\\n'.join(info)\n\n def build_computer(self, model):\n if (model == MINI14):\n return self.MacMini14()\n else:\n print(\"I dont't know how to build {}\".format(model))\n\nif __name__ == '__main__':\n afac = AppleFactory()\n mac_mini = afac.build_computer(MINI14)\n print(mac_mini)\n" }, { "path": "chapter2/builder.py", "content": "# coding: utf-8\n\nfrom enum import Enum\nimport time\n\nPizzaProgress = Enum('PizzaProgress', 'queued preparation baking ready')\nPizzaDough = Enum('PizzaDough', 'thin thick')\nPizzaSauce = Enum('PizzaSauce', 'tomato creme_fraiche')\nPizzaTopping = Enum('PizzaTopping', 'mozzarella double_mozzarella bacon ham mushrooms red_onion oregano')\nSTEP_DELAY = 3 # 考虑是示例，单位为秒\n\n\nclass Pizza:\n\n def __init__(self, name):\n self.name = name\n self.dough = None\n self.sauce = None\n self.topping = []\n\n def __str__(self):\n return self.name\n\n def prepare_dough(self, dough):\n self.dough = dough\n print('preparing the {} dough of your {}...'.format(self.dough.name, self))\n time.sleep(STEP_DELAY)\n print('done with the {} dough'.format(self.dough.name))\n\n\nclass MargaritaBuilder:\n\n def __init__(self):\n self.pizza = Pizza('margarita')\n self.progress = PizzaProgress.queued\n self.baking_time = 5 # 考虑是示例，单位为秒\n\n def prepare_dough(self):\n self.progress = PizzaProgress.preparation\n self.pizza.prepare_dough(PizzaDough.thin)\n\n def add_sauce(self):\n print('adding the tomato sauce to your margarita...')\n self.pizza.sauce = PizzaSauce.tomato\n time.sleep(STEP_DELAY)\n print('done with the tomato sauce')\n\n def add_topping(self):\n print('adding the topping (double mozzarella, oregano) to your margarita')\n self.pizza.topping.append([i for i in\n (PizzaTopping.double_mozzarella, PizzaTopping.oregano)])\n time.sleep(STEP_DELAY)\n print('done with the topping (double mozzarrella, oregano)')\n\n def bake(self):\n self.progress = PizzaProgress.baking\n print('baking your margarita for {} seconds'.format(self.baking_time))\n time.sleep(self.baking_time)\n self.progress = PizzaProgress.ready\n print('your margarita is ready')\n\n\nclass CreamyBaconBuilder:\n\n def __init__(self):\n self.pizza = Pizza('creamy bacon')\n self.progress = PizzaProgress.queued\n self.baking_time = 7 # 考虑是示例，单位为秒\n\n def prepare_dough(self):\n self.progress = PizzaProgress.preparation\n self.pizza.prepare_dough(PizzaDough.thick)\n\n def add_sauce(self):\n print('adding the crème fraîche sauce to your creamy bacon')\n self.pizza.sauce = PizzaSauce.creme_fraiche\n time.sleep(STEP_DELAY)\n print('done with the crème fraîche sauce')\n\n def add_topping(self):\n print('adding the topping (mozzarella, bacon, ham, mushrooms, red onion, oregano) to your creamy bacon')\n self.pizza.topping.append([t for t in\n (PizzaTopping.mozzarella, PizzaTopping.bacon,\n PizzaTopping.ham, PizzaTopping.mushrooms,\n PizzaTopping.red_onion, PizzaTopping.oregano)])\n time.sleep(STEP_DELAY)\n print('done with the topping (mozzarella, bacon, ham, mushrooms, red onion, oregano)')\n\n def bake(self):\n self.progress = PizzaProgress.baking\n print('baking your creamy bacon for {} seconds'.format(self.baking_time))\n time.sleep(self.baking_time)\n self.progress = PizzaProgress.ready\n print('your creamy bacon is ready')\n\n\nclass Waiter:\n\n def __init__(self):\n self.builder = None\n\n def construct_pizza(self, builder):\n self.builder = builder\n [step() for step in (builder.prepare_dough,\n builder.add_sauce, builder.add_topping, builder.bake)]\n\n @property\n def pizza(self):\n return self.builder.pizza\n\n\ndef validate_style(builders):\n try:\n pizza_style = input('What pizza would you like, [m]argarita or [c]reamy bacon? ')\n builder = builders[pizza_style]()\n valid_input = True\n except KeyError as err:\n print('Sorry, only margarita (key m) and creamy bacon (key c) are available')\n return (False, None)\n return (True, builder)\n\n\ndef main():\n builders = dict(m=MargaritaBuilder, c=CreamyBaconBuilder)\n valid_input = False\n while not valid_input:\n valid_input, builder = validate_style(builders)\n print()\n waiter = Waiter()\n waiter.construct_pizza(builder)\n pizza = waiter.pizza\n print()\n print('Enjoy your {}!'.format(pizza))\n\nif __name__ == '__main__':\n main()\n" }, { "path": "chapter2/builder2.py", "content": "# coding: utf-8\n\n\nclass Pizza:\n\n def __init__(self, builder):\n self.garlic = builder.garlic\n self.extra_cheese = builder.extra_cheese\n\n def __str__(self):\n garlic = 'yes' if self.garlic else 'no'\n cheese = 'yes' if self.extra_cheese else 'no'\n info = ('Garlic: {}'.format(garlic), 'Extra cheese: {}'.format(cheese))\n return '\\n'.join(info)\n\n class PizzaBuilder:\n\n def __init__(self):\n self.extra_cheese = False\n self.garlic = False\n\n def add_garlic(self):\n self.garlic = True\n return self\n\n def add_extra_cheese(self):\n self.extra_cheese = True\n return self\n\n def build(self):\n return Pizza(self)\n\nif __name__ == '__main__':\n pizza = Pizza.PizzaBuilder().add_garlic().add_extra_cheese().build()\n print(pizza)\n" }, { "path": "chapter2/computer-builder.py", "content": "# coding: utf-8\n\n\nclass Computer:\n\n def __init__(self, serial_number):\n self.serial = serial_number\n self.memory = None # 单位为GB\n self.hdd = None # 单位为GB\n self.gpu = None\n\n def __str__(self):\n info = ('Memory: {}GB'.format(self.memory),\n 'Hard Disk: {}GB'.format(self.hdd),\n 'Graphics Card: {}'.format(self.gpu))\n return '\\n'.join(info)\n\n\nclass ComputerBuilder:\n\n def __init__(self):\n self.computer = Computer('AG23385193')\n\n def configure_memory(self, amount):\n self.computer.memory = amount\n\n def configure_hdd(self, amount):\n self.computer.hdd = amount\n\n def configure_gpu(self, gpu_model):\n self.computer.gpu = gpu_model\n\n\nclass HardwareEngineer:\n\n def __init__(self):\n self.builder = None\n\n def construct_computer(self, memory, hdd, gpu):\n self.builder = ComputerBuilder()\n [step for step in (self.builder.configure_memory(memory),\n self.builder.configure_hdd(hdd),\n self.builder.configure_gpu(gpu))]\n\n @property\n def computer(self):\n return self.builder.computer\n\n\ndef main():\n engineer = HardwareEngineer()\n engineer.construct_computer(hdd=500, memory=8, gpu='GeForce GTX 650 Ti')\n computer = engineer.computer\n print(computer)\n\nif __name__ == '__main__':\n main()\n" }, { "path": "chapter3/clone.py", "content": "import copy\n\n\nclass A:\n\n def __init__(self):\n self.x = 18\n self.msg = 'Hello'\n\n\nclass B(A):\n\n def __init__(self):\n A.__init__(self)\n self.y = 34\n\n def __str__(self):\n return '{}, {}, {}'.format(self.x, self.msg, self.y)\n\nif __name__ == '__main__':\n b = B()\n c = copy.deepcopy(b)\n print([str(i) for i in (b, c)])\n print([i for i in (b, c)])\n" }, { "path": "chapter3/prototype.py", "content": "# coding: utf-8\n\nimport copy\nfrom collections import OrderedDict\n\n\nclass Book:\n\n def __init__(self, name, authors, price, **rest):\n '''rest的例子有：出版商，长度，标签，出版日期'''\n self.name = name\n self.authors = authors\n self.price = price # 单位为美元\n self.__dict__.update(rest)\n\n def __str__(self):\n mylist = []\n ordered = OrderedDict(sorted(self.__dict__.items()))\n for i in ordered.keys():\n mylist.append('{}: {}'.format(i, ordered[i]))\n if i == 'price':\n mylist.append('$')\n mylist.append('\\n')\n return ''.join(mylist)\n\n\nclass Prototype:\n\n def __init__(self):\n self.objects = dict()\n\n def register(self, identifier, obj):\n self.objects[identifier] = obj\n\n def unregister(self, identifier):\n del self.objects[identifier]\n\n def clone(self, identifier, **attr):\n found = self.objects.get(identifier)\n if not found:\n raise ValueError('Incorrect object identifier: {}'.format(identifier))\n obj = copy.deepcopy(found)\n obj.__dict__.update(attr)\n return obj\n\n\ndef main():\n b1 = Book('The C Programming Language', ('Brian W. Kernighan', 'Dennis M.Ritchie'), price=118, publisher='Prentice Hall',\n length=228, publication_date='1978-02-22', tags=('C', 'programming', 'algorithms', 'data structures'))\n\n prototype = Prototype()\n cid = 'k&r-first'\n prototype.register(cid, b1)\n b2 = prototype.clone(cid, name='The C Programming Language(ANSI)', price=48.99,\n length=274, publication_date='1988-04-01', edition=2)\n\n for i in (b1, b2):\n print(i)\n print('ID b1 : {} != ID b2 : {}'.format(id(b1), id(b2)))\n\nif __name__ == '__main__':\n main()\n" }, { "path": "chapter4/adapter.py", "content": "from external import Synthesizer, Human\n\n\nclass Computer:\n\n def __init__(self, name):\n self.name = name\n\n def __str__(self):\n return 'the {} computer'.format(self.name)\n\n def execute(self):\n return 'executes a program'\n\n\nclass Adapter:\n\n def __init__(self, obj, adapted_methods):\n self.obj = obj\n self.__dict__.update(adapted_methods)\n\n def __str__(self):\n return str(self.obj)\n\n\ndef main():\n objects = [Computer('Asus')]\n synth = Synthesizer('moog')\n objects.append(Adapter(synth, dict(execute=synth.play)))\n human = Human('Bob')\n objects.append(Adapter(human, dict(execute=human.speak)))\n\n for i in objects:\n print('{} {}'.format(str(i), i.execute()))\n\nif __name__ == \"__main__\":\n main()\n" }, { "path": "chapter4/external.py", "content": "class Synthesizer:\n\n def __init__(self, name):\n self.name = name\n\n def __str__(self):\n return 'the {} synthesizer'.format(self.name)\n\n def play(self):\n return 'is playing an electronic song'\n\n\nclass Human:\n\n def __init__(self, name):\n self.name = name\n\n def __str__(self):\n return '{} the human'.format(self.name)\n\n def speak(self):\n return 'says hello'\n" }, { "path": "chapter5/mymath.py", "content": "# coding: utf-8\n\nimport functools\n\n\ndef memoize(fn):\n known = dict()\n\n @functools.wraps(fn)\n def memoizer(*args):\n if args not in known:\n known[args] = fn(*args)\n return known[args]\n\n return memoizer\n\n\n@memoize\ndef nsum(n):\n '''返回前n个数字的和'''\n assert(n >= 0), 'n must be >= 0'\n return 0 if n == 0 else n + nsum(n-1)\n\n\n@memoize\ndef fibonacci(n):\n '''返回斐波那契数列的第n个数'''\n assert(n >= 0), 'n must be >= 0'\n return n if n in (0, 1) else fibonacci(n-1) + fibonacci(n-2)\n\nif __name__ == '__main__':\n from timeit import Timer\n measure = [{'exec': 'fibonacci(100)', 'import': 'fibonacci',\n 'func': fibonacci}, {'exec': 'nsum(200)', 'import': 'nsum',\n 'func': nsum}]\n for m in measure:\n t = Timer('{}'.format(m['exec']), 'from __main__ import \\\n {}'.format(m['import']))\n print('name: {}, doc: {}, executing: {}, time: \\\n {}'.format(m['func'].__name__, m['func'].__doc__,\n m['exec'], t.timeit()))\n" }, { "path": "chapter6/facade.py", "content": "# coding: utf-8\n\nfrom enum import Enum\nfrom abc import ABCMeta, abstractmethod\n\nState = Enum('State', 'new running sleeping restart zombie')\n\n\nclass User:\n pass\n\n\nclass Process:\n pass\n\n\nclass File:\n pass\n\n\nclass Server(metaclass=ABCMeta):\n\n @abstractmethod\n def __init__(self):\n pass\n\n def __str__(self):\n return self.name\n\n @abstractmethod\n def boot(self):\n pass\n\n @abstractmethod\n def kill(self, restart=True):\n pass\n\n\nclass FileServer(Server):\n\n def __init__(self):\n '''初始化文件服务进程要求的操作'''\n self.name = 'FileServer'\n self.state = State.new\n\n def boot(self):\n print('booting the {}'.format(self))\n '''启动文件服务进程要求的操作'''\n self.state = State.running\n\n def kill(self, restart=True):\n print('Killing {}'.format(self))\n '''杀死文件服务进程要求的操作'''\n self.state = State.restart if restart else State.zombie\n\n def create_file(self, user, name, permissions):\n '''检查访问权限的有效性、用户权限，等等'''\n\n print(\"trying to create the file '{}' for user '{}' with permissions {}\".format(name, user, permissions))\n\n\nclass ProcessServer(Server):\n\n def __init__(self):\n '''初始化进程服务进程要求的操作'''\n self.name = 'ProcessServer'\n self.state = State.new\n\n def boot(self):\n print('booting the {}'.format(self))\n '''启动进程服务进程要求的操作'''\n self.state = State.running\n\n def kill(self, restart=True):\n print('Killing {}'.format(self))\n '''杀死进程服务进程要求的操作'''\n self.state = State.restart if restart else State.zombie\n\n def create_process(self, user, name):\n '''检查用户权限、生成PID，等等'''\n\n print(\"trying to create the process '{}' for user '{}'\".format(name, user))\n\n\nclass WindowServer:\n pass\n\n\nclass NetworkServer:\n pass\n\n\nclass OperatingSystem:\n\n '''外观'''\n\n def __init__(self):\n self.fs = FileServer()\n self.ps = ProcessServer()\n\n def start(self):\n [i.boot() for i in (self.fs, self.ps)]\n\n def create_file(self, user, name, permissions):\n return self.fs.create_file(user, name, permissions)\n\n def create_process(self, user, name):\n return self.ps.create_process(user, name)\n\n\ndef main():\n os = OperatingSystem()\n os.start()\n os.create_file('foo', 'hello', '-rw-r-r')\n os.create_process('bar', 'ls /tmp')\n\nif __name__ == '__main__':\n main()\n" }, { "path": "chapter7/flyweight.py", "content": "# coding: utf-8\n\nimport random\nfrom enum import Enum\n\nTreeType = Enum('TreeType', 'apple_tree cherry_tree peach_tree')\n\n\nclass Tree:\n pool = dict()\n\n def __new__(cls, tree_type):\n obj = cls.pool.get(tree_type, None)\n if not obj:\n obj = object.__new__(cls)\n cls.pool[tree_type] = obj\n obj.tree_type = tree_type\n return obj\n\n def render(self, age, x, y):\n print('render a tree of type {} and age {} at ({}, {})'.format(self.tree_type, age, x, y))\n\n\ndef main():\n rnd = random.Random()\n age_min, age_max = 1, 30 # 单位为年\n min_point, max_point = 0, 100\n tree_counter = 0\n\n for _ in range(10):\n t1 = Tree(TreeType.apple_tree)\n t1.render(rnd.randint(age_min, age_max),\n rnd.randint(min_point, max_point),\n rnd.randint(min_point, max_point))\n tree_counter += 1\n\n for _ in range(3):\n t2 = Tree(TreeType.cherry_tree)\n t2.render(rnd.randint(age_min, age_max),\n rnd.randint(min_point, max_point),\n rnd.randint(min_point, max_point))\n tree_counter += 1\n\n for _ in range(5):\n t3 = Tree(TreeType.peach_tree)\n t3.render(rnd.randint(age_min, age_max),\n rnd.randint(min_point, max_point),\n rnd.randint(min_point, max_point))\n tree_counter += 1\n\n print('trees rendered: {}'.format(tree_counter))\n print('trees actually created: {}'.format(len(Tree.pool)))\n\n t4 = Tree(TreeType.cherry_tree)\n t5 = Tree(TreeType.cherry_tree)\n t6 = Tree(TreeType.apple_tree)\n print('{} == {}? {}'.format(id(t4), id(t5), id(t4) == id(t5)))\n print('{} == {}? {}'.format(id(t5), id(t6), id(t5) == id(t6)))\n\nif __name__ == '__main__':\n main()\n" }, { "path": "chapter8/mvc.py", "content": "quotes = ('A man is not complete until he is married. Then he is finished.',\n 'As I said before, I never repeat myself.',\n 'Behind a successful man is an exhausted woman.',\n 'Black holes really suck...', 'Facts are stubborn things.')\n\n\nclass QuoteModel:\n\n def get_quote(self, n):\n try:\n value = quotes[n]\n except IndexError as err:\n value = 'Not found!'\n return value\n\n\nclass QuoteTerminalView:\n\n def show(self, quote):\n print('And the quote is: \"{}\"'.format(quote))\n\n def error(self, msg):\n print('Error: {}'.format(msg))\n\n def select_quote(self):\n return input('Which quote number would you like to see?')\n\n\nclass QuoteTerminalController:\n\n def __init__(self):\n self.model = QuoteModel()\n self.view = QuoteTerminalView()\n\n def run(self):\n valid_input = False\n while not valid_input:\n n = self.view.select_quote()\n try:\n n = int(n)\n except ValueError as err:\n self.view.error(\"Incorrect index '{}'\".format(n))\n else:\n valid_input = True\n quote = self.model.get_quote(n)\n self.view.show(quote)\n\n\ndef main():\n controller = QuoteTerminalController()\n while True:\n controller.run()\n\nif __name__ == '__main__':\n main()\n" }, { "path": "chapter9/lazy.py", "content": "# coding: utf-8\n\n\nclass LazyProperty:\n\n def __init__(self, method):\n self.method = method\n self.method_name = method.__name__\n # print('function overriden: {}'.format(self.method))\n # print(\"function's name: {}\".format(self.method_name))\n\n def __get__(self, obj, cls):\n if not obj:\n return None\n value = self.method(obj)\n # print('value {}'.format(value))\n setattr(obj, self.method_name, value)\n return value\n\n\nclass Test:\n\n def __init__(self):\n self.x = 'foo'\n self.y = 'bar'\n self._resource = None\n\n @LazyProperty\n def resource(self):\n print('initializing self._resource which is: {}'.format(self._resource))\n self._resource = tuple(range(5)) # 代价大的\n return self._resource\n\n\ndef main():\n t = Test()\n print(t.x)\n print(t.y)\n # 做更多的事情。。。\n print(t.resource)\n print(t.resource)\n\nif __name__ == '__main__':\n main()\n" }, { "path": "chapter9/proxy.py", "content": "# coding: utf-8\n\n\nclass SensitiveInfo:\n\n def __init__(self):\n self.users = ['nick', 'tom', 'ben', 'mike']\n\n def read(self):\n print('There are {} users: {}'.format(len(self.users), ' '.join(self.users)))\n\n def add(self, user):\n self.users.append(user)\n print('Added user {}'.format(user))\n\n\nclass Info:\n\n '''SensitiveInfo的保护代理'''\n\n def __init__(self):\n self.protected = SensitiveInfo()\n self.secret = '0xdeadbeef'\n\n def read(self):\n self.protected.read()\n\n def add(self, user):\n sec = input('what is the secret? ')\n self.protected.add(user) if sec == self.secret else print(\"That's wrong!\")\n\n\ndef main():\n info = Info()\n while True:\n print('1. read list |==| 2. add user |==| 3. quit')\n key = input('choose option: ')\n if key == '1':\n info.read()\n elif key == '2':\n name = input('choose username: ')\n info.add(name)\n elif key == '3':\n exit()\n else:\n print('unknown option: {}'.format(key))\n\nif __name__ == '__main__':\n main()\n" } ]