编程之道 2

dragon_kai

design
book three
thus spake the master programmer:
编程大师如是说：
\"when program is being tested, it is too late to make design changes.\"
“程序被测试时再去改变它的设计已经太晚了。”
3.1
there once was a man who went to a computer trade show. each day as he enter
ed, the man told the guard at the door:
曾经有一个人参加计算机展览，每天他进门时都对门卫说：
\"i am a great thief, renowned for my feats of shoplifting. be forewarned, fo
r this trade show shall not escape unplundered.\"
“先警告你，我是偷盗高手，我入室偷盗的本领闻名遐迩。这次展览会也再劫难逃。”

this speech disturbed the guard greatly, because there were millions of doll
ars of computer equipment inside, so he watched the man carefully. but the m
an merely wandered from booth to booth, humming quietly to himself.
警卫因此大动干戈，因为里面有价值百万的计算机设备，所以他牢牢盯紧了这个人，但
是这个人只是从一个摊位逛到另一个摊位，一边平静地喃喃自语。
when the man left, the guard took him aside and searched his clothes, but no
thing was to be found.
当这个人离开时，警卫搜了他的身，但是什么也没有发现。
on the next day of the trade show, the man returned and chided the guard say
ing: \"i escaped with a vast booty yesterday, but today will be even better.\"
so the guard watched him ever more closely, but to no avail.
展览会的第二天，这个人又对警卫说：“昨天我满载而归，但是今天我会收获更大。”
所以警卫更加小心地盯紧他，但是这样做完全于事无补。
on the final day of the trade show, the guard could restrain his curiosity n
o longer. \"sir thief,\" he said, \"i am so perplexed, i cannot live in peace.
please enlighten me. what is it that you are stealing?\"
展览会的最后一天，警卫再也不能忍住他的好奇心了。“小偷先生，”他说，“ 你说我
惊慌不安，请告诉我，你到底偷了什么？”。
the man smiled. \"i am stealing ideas,\" he said.
这个人笑笑说：“我在偷想法。”
3.2
there once was a master programmer who wrote unstructured programs. a novice
programmer, seeking to imitate him, also began to write unstructured progra
ms. when the novice asked the master to evaluate his progress, the master cr
iticized him for writing unstructured programs, saying: \"what is appropriate
for the master is not appropriate for the novice. you must understand the t
ao before transcending structure.\"
有一位编程大师，他写非结构化的程序，一位初学者刻意模仿他，也写非结构化的程序
。当他让大师看他的进步时，大师批评了他的非结构化程序：“ 对一位编程大师合适的
东西未必对一个初学者同样合适，在超越结构化之前，你必须理解编程之道。”
3.3
there was once a programmer who was attached to the court of the warlord of
wu. the warlord asked the programmer: \"which is easier to design: an account
ing package or an operating system?\"
###有人问一位程序员，“一个财务软件和一个操作系统哪个更容易设计？”
\"an operating system,\" replied the programmer.
“是操作系统”，这位程序员回答说。
the warlord uttered an exclamation of disbelief. \"surely an accounting packa
ge is trivial next to the complexity of an operating system,\" he said.
此人大惑不解。他说：“显然一个财务软件比起操作系统来说其复杂性是微不足道的”
。
\"not so,\" said the programmer, \"when designing an accounting package, the pr
ogrammer operates as a mediator between people having different ideas: how i
t must operate, how its reports must appear, and how it must conform to the
tax laws. by contrast, an operating system is not limited my outside appeara
nces. when designing an operating system, the programmer seeks the simplest
harmony between machine and ideas. this is why an operating system is easier
to design.\"
程序员说：“不，设计财务软件时，一个程序员必须成为持不同意见的用户与计算机的
一个中介，他必须了解用户的操作习惯，报表要是什么形式，如何遵循税法。相反，一
个操作系统完全与这些外部的东西无关。设计操作系统，程序员只需要达到自己的设想
与机器之间的简单的和谐。这就是为什么操作系统反而比财务软件更容易设计。”
the warlord of wu nodded and smiled. \"that is all good and well, but which i
s easier to debug?\"
这些人笑着说。“不错，但是哪一个更容易调试呢？”
the programmer made no reply.
程序员没有回答。
3.4
a manager went to the master programmer and showed him the requirements docu
ment for a new application. the manager asked the master: \"how long will it
take to design this system if i assign five programmers to it?\"
一个项目经理带给编程大师一个项目的需求，然后问大师：“如果我给你5个程序员，要
多少时间设计这个项目？”
\"it will take one year,\" said the master promptly.
“一年”，大师说。
\"but we need this system immediately or even sooner! how long will it take i
t i assign ten programmers to it?\"
“但是我们等不了那么长时间，越快越好，如果10程序员呢？”
the master programmer frowned. \"in that case, it will take two years.\"
大师皱了一下眉头说：“那就要花2年”。
\"and what if i assign a hundred programmers to it?\"
“那，100年程序员呢？”
the master programmer shrugged. \"then the design will never be completed,\" h
e said.
大师耸了耸肩说：“那这个项目就永远完不成了。”
----------------------------------------------------------------------------
----
coding
book four
thus spake the master programmer:
编程大师如是说：
\"a well-written program is its own heaven;
a poorly-written program is its own hell.\"
“写的好的程序是它自己的天堂，写的不好的程序是它自己的地狱”
4.1
a program should be light and agile, its subroutines connected like a string
s of pearls. the spirit and intent of the program should be retained through
out. there should be neither too little nor too much, neither needless loops
nor useless variables, neither lack of structure nor overwhelming rigidity.

一个程序应该是轻灵自由的，它的子过程就象串在一根线上的珍珠。自始至终，目标明
确。增之一字节则太长，减之一字节则太短。既没有不必要的循环也没有没有被引用的
变量，既不缺少结构化也不至于僵硬呆板。
a program should follow the law of least astonishment. what is this law? it
is simply that the program should always respond to the user in the way that
astonishes him least.
一个程序应该遵循``最小惊讶原则''，什么是``最小惊讶原则''？就是说一个程序应该
最小程度地引起用户的惊讶。
a program, no matter how complex, should act as a single unit. the program s
hould be directed by the logic within rather than by outward appearances.
无论一个程序无论有多么复杂都应该是一个单一的整体。程序是被它的内部逻辑所指引
而不是它的外观表现。
if the program fails in these requirements, it will be in a state of disorde
r and confusion. the only way to correct this is to rewrite the program.
如果一个程序不能满足所要的需求，它就会处于混乱无序的状态中。唯一的出路就是重
写这个程序。
4.2
a novice asked the master: \"i have a program that sometimes runs and sometim
es aborts. i have followed the rules of programming, yet i am totally baffle
d. what is the reason for this?\"
一个初学者问大师：“我的一个程序有时正常有时不正常。我已经完全遵循编程的规则
，而且我完全被它弄糊涂了，到底是什么原因会导致这样呢？”
the master replied: \"you are confused because you do not understand the tao.
only a fool expects rational behavior from his fellow humans. why do you ex
pect it from a machine that humans have constructed? computers simulate dete
rminism; only the tao is perfect.
大师说：“你困惑是因为你不了解道。只有傻瓜才会相信只要遵循别人所说就能得到想
当然的结果。为什么你要从一个人类自己构造的机器中去得到想当然的结果呢？计算机
只是决定论的产物；只有道才是唯一完美的。
the rules of programming are transitory; only the tao is eternal. therefore
you must contemplate the tao before you receive enlightenment.\"
任何编程的规则都只适合于特定的情况，只有道才是永恒不变的。所以在你受到指引之
前要先去思考道。”
\"but how will i know when i have received enlightenment?\" asked the novice.
“但是我怎么知道我何时受到指引呢？”
\"your program will then run correctly,\" replied the master.
“当你的程序正确运行时”。大师说。
4.3
a master was explaining the nature of the tao to one of his novices, \"the ta
o is embodied in all software -- regardless of how insignificant,\" said the
master.
初学者请大师解释“道法自然”。大师说：“道存在于任何软件中－－无论是多么没有
意义的软件”。
\"is the tao in a hand-held calculator?\" asked the novice.
“难道也存在于手持式的计算嚣里？”，初学者问。
\"it is,\" came the reply.
“是的，”
\"is the tao in a video game?\" continued the novice.
“也在游戏机里？”，初学者又问到。
\"it is even in a video game,\" said the master.
“是的，甚至也存在于游戏机里”。大师说。
\"and is the tao in the dos for a personal computer?\"
“也存在于个人计算机的dos里吗？”
the master coughed and shifted his position slightly. \"the lesson is over fo
r today,\" he said.
大师咳嗽了一声，稍微动了一下，说，“今天的课就到这里”。
4.4
price wang's programmer was coding software. his fingers danced upon the key
board. the program compiled without an error message, and the program ran li
ke a gentle wind.
###编程大师编写软件时，手指在键盘上快速飞舞。程序编译时没有一条错误信息，程序
运行起来就象一阵微风吹过。
excellent!\" the price exclaimed, \"your technique is faultless!\"
太精彩了！你的技巧已经无可挑剔了。
\"technique?\" said the programmer, turning from his terminal, \"what i follow
is the tao -- beyond all technique. when i first began to program i would se
e before me the whole program in one mass. after three years i no longer saw
this mass. instead, i used subroutines. but now i see nothing. my whole bei
ng exists in a formless void. my senses are idle. my spirit, free to work wi
thout a plan, follows its own instinct. in short, my program writes itself.
true, sometimes there are difficult problems. i see them coming, i slow down
, i watch silently. then i change a single line of code and the difficulties
vanish like puffs of idle smoke. i then compile the program. i sit still an
d let the joy of the work fill my being. i close my eyes for a moment and th
en log off.\"
“技巧？”，大师转过身说，“我所遵循的是道--它超乎所有的技巧。当我开始编程时
我看到的是整个一大块的程序，三年后我看到的是子过程。现在我什么也看不到了。我
的整个存在是没有任何形式的虚无。我感觉很悠闲，总之，事实上是我的程序自己在写
，有时我看到一些问题，我看到它们，就停下来静静地观察它们，然后我改变了一行代
码，难题就象一阵轻烟一样化为乌有。然后我编译程序。坐在那里享受工作的喜悦。闭
了一会眼睛然后退出系统。
price wang said, \"would that all of my programmers were as wise!\"
“什么时候我的程序员才能都达到这样的境界!”
mainteance
book five
thus spake the master programmer:
编程大师如是说：
\"though a program be but three lines long, someday it will have to be mainta
ined.\"
“既使一个程序只有三行长，也总有一天需要去维护它”
5.1
a well-used door needs no oil on its hinges.
a swift-flowing steam does no grow stagnant.
neither sound nor thoughts can travel through a vacuum.
software rots if not used.
经常使用的门不需要往门轴里上油。
流动的东西就不会停滞不前。
流水不腐，户枢不蠹。--王磊
声音和思想都不能在真空里传播。
软件不用就会腐朽。
these are great mysteries.
5.2
a manager asked a programmer how long it would take him to finish the progra
m on which he was working. \"i will be finished tomorrow,\" the programmer pro
mptly replied.
经理问程序员要多长时间才能完成他的项目。“明天”
\"i think you are being unrealistic,\" said the manager. \"truthfully, how long
will it take?\"
“太不着边际了，老实说，要多久？”
the programmer thought for a moment. \"i have some features that i wish to ad
d. this will take at least two weeks,\" he finally said.
程序员想了一想说。“还有一些新的功能要加进去，可能至少要两个星期吧。”
\"even that is too much to expect,\" insisted the manager, \"i will be satisfie
d if you simply tell me when the program is complete.\"
“即使两个星期恐怕也太夸张了，什么时候你只要告诉我说程序已经完成就好了。”
the programmer agreed to this.
several years slated, the manager retired. on the way to his retirement lunc
h, he discovered the programmer asleep at his terminal. he had been programm
ing all night.
几年后，这个经理已经退休了，在他的离职午餐上，他发现这些程序员在他的终端前睡
着了，他整夜都在编程。
5.3
a novice programmer was once assigned to code a simple financial package.
一个初学者被要求编写一个财务软件。
the novice worked furiously for many days, but when his master reviewed his
program, he discovered that it contained a screen editor, a set of generaliz
ed graphics routines, and artificial intelligence interface, but not the sli
ghtest mention of anything financial.
他疯狂地工作了很多天，但他的主管检视他的程序时发现，它写了一个编辑嚣，一个图
形程序集，和人工智能的界面，但是看不到任何跟财务有关的东西。
when the master asked about this, the novice became indignant. \"don't be so
impatient,\" he said, \"i'll put the financial stuff in eventually.\"
主管要求解释时，程序员被激怒了：“你太没耐心了，我会在最后写财务的部分。”
5.4
does a good farmer neglect a crop he has planted?
does a good teacher overlook even the most humble student?
does a good father allow a single child to starve?
does a good programmer refuse to maintain his code?
一个好的农民不会不管他的庄稼。
一个好的老师不会不管哪怕是最差的学生。
一个好的父亲不会让他的任何一个孩子挨饿。
一个好的程序员不应拒绝维护他的程序。
----------------------------------------------------------------------------
----
management
book six
thus spake the master programmer:
编程大师如是说：
\"let the programmer be many and the managers few -- then all will be product
ive.\"
“增加程序员，减少经理--这样他们都可提高效率。”
6.1
when managers hold endless meetings, the programmers write games. when accou
ntants talk of quarterly profits, the development budget is about to be cut.
when senior scientists talk blue sky, the clouds are about to roll in.
经理们忙于无休无止的会议时，程序员们在写游戏。财务主管在谈论季度盈利时开发预
算将会被削减。当老科学家在谈天空的蓝色时，云团蜂拥而至。
truly, this is not the tao of programming.
这不是编程之道。
when managers make commitments, game programs are ignored. when accountants
make long-range plans, harmony and order are about to be restored. when seni
or scientists address the problems at hand, the problems will soon be solved
.
经理分配任务时不会包括游戏，会计师做长期计划时，应该做到面面俱到，皆大欢喜。
科学家提出一个问题，就会很快得到解决。
truly, this is the tao of programming.
这才是编程之道。
6.2
why are programmers non-productive? because their time is wasted in meetings
.
为什么程序员没有效率，因为他们把时间都浪费在开会上了。
why are programmers rebellious? because the management interferes too much.
为什么程序员难于管理？因为管理者的干预太多了。
why are the programmers resigning one by one? because they are burnt out.
为什么程序员一个接一个地辞职，因为他们累坏了。
having worked for poor management, they no longer value their jobs.
在糟糕的管理下工作，他们享受不到工作的乐趣。
6.3
a manager was about to be fired, but a programmer who worked for him invente
d a new program that became popular and sold well. as a result, the manager
retained his job.
一个经理将被解雇，但他手下的一个程序员写了一个流行的软件并且销路很旺。所以经
理保住了他的工作。
the manager tried to give the programmer a bonus, but the programmer refused
it, saying, \"i wrote the program because i though it was an interesting con
cept, and thus i expect no reward.\"
经理为程序员分红，但程序员拒绝了，他说：“我写程序是因为写程序很有趣，所以我
并没想过得资金”。
the manager, upon hearing this, remarked, \"this programmer, though he holds
a position of small esteem, understands well the proper duty of an employee.
lets promote him to the exalted position of management consultant!\"
这位经理说，“这位程序员，不管他现在是什么位置，他都能理解一个雇员的职责所在
。我们要把他提升为管理顾问”。
but when told this, the programmer once more refused, saying, \"i exist so th
at i can program. if i were promoted, i would do nothing but waste everyone'
s time. can i go now? i have a program that i'm working one.\"
这位程序员又一次拒绝了，他说：“我是一个程序员所以我可以编程，如果我被提升了
，除了浪费别人的时间什么也做不了，现在我可以走了吗？我还有一个程序没写完。”

6.4
a manger went to his programmers and told them: \"as regards to your work hou
rs: you are going to have to come in at nine in the morning and leave at fiv
e in the afternoon.\" at this, all of them became angry and several resigned
on the spot.
经理对程序员说，“你们的工作时间是早上9点到正午点。”，所有的程序员都很不满。

so the manager said: \"all right, in that case you may set your own working h
ours, as long as you finish your projects on schedule.\" the programmers, now
satisfied, began to come in a noon and work to the wee hours of the morning
.
经理又说：“好吧，那随你们的便，只要能按时完成任务。”，程序员们这下满意了，
他们中午上班，一直工作到凌晨。