Python程序员的进化史（ 程序员既要写好代码，又要写好文档）

Python程序员的进化史（ 程序员既要写好代码，又要写好文档）

不久前，在互联网上出现了一篇有趣的文章，讲的是对于同一个问题，不同层次的程序员编出的 Python 代码显示出了不同的风格，代码都很简单，有趣。

编程新手def factorial(x): if x == 0: return 1 else: return x * factorial(x - 1)print factorial(6)一年编程经验（学 Pascal 的）def factorial(x): result = 1 i = 2 while i <= x: result = result * i i = i + 1 return resultprint factorial(6)一年编程经验（学 C 的）def fact(x): #{ result = i = 1; while (i <= x): #{ result *= i; i += 1; #} return result;#}print(fact(6))一年编程经验（读过 SICP）@tailcalldef fact(x, acc=1): if (x > 1): return (fact((x - 1), (acc * x))) else: return accprint(fact(6))一年编程经验（Python）def Factorial(x): res = 1 for i in xrange(2, x + 1): res *= i return resprint Factorial(6)懒惰的 Python 程序员def fact(x): return x > 1 and x * fact(x - 1) or 1print fact(6)更懒的 Python 程序员f = lambda x: x and x * f(x - 1) or 1print f(6)Python 专家import operator as opimport functional as ffact = lambda x: f.foldl(op.mul, 1, xrange(2, x + 1))print fact(6)Python 黑客import sys@tailcalldef fact(x, acc=1): if x: return fact(x.__sub__(1), acc.__mul__(x)) return accsys.stdout.write(str(fact(6)) + '\n')专家级程序员import c_mathfact = c_math.factprint fact(6)大英帝国程序员import c_mathsfact = c_maths.factprint fact(6)Web 设计人员def factorial(x): #------------------------------------------------- #--- 这段代码是从 Math Vault 那弄过来滴--- #--- 计算阶乘 （C）亚瑟·史密斯 1999年--- #------------------------------------------------- result = str(1) i = 1 #谢谢亚当 while i <= x: #result = result * i #It's faster to use *= #result = str(result * result + i) #result = int(result *= i) #?????? result str(int(result) * i) #result = int(str(result) * i) i = i + 1 return resultprint factorial(6)Unix 程序员import osdef fact(x): os.system('factorial ' + str(x))fact(6)Windows 程序员NULL = Nonedef CalculateAndPrintFactorialEx(dwNumber, hOutputDevice, lpLparam, lpWparam, lpsscSecurity, *dwReserved): if lpsscSecurity != NULL: return NULL #Not implemented dwResult = dwCounter = 1 while dwCounter <= dwNumber: dwResult *= dwCounter dwCounter += 1 hOutputDevice.write(str(dwResult)) hOutputDevice.write('\n') return 1import sysCalculateAndPrintFactorialEx(6, sys.stdout, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL)企业级程序员def new(cls, *args, **kwargs): return cls(*args, **kwargs) class Number(object): pass class IntegralNumber(int, Number): def toInt(self): return new (int, self) class InternalBase(object): def __init__(self, base): self.base = base.toInt() def getBase(self): return new (IntegralNumber, self.base) class MathematicsSystem(object): def __init__(self, ibase): Abstract @classmethod def getInstance(cls, ibase): try: cls.__instance except AttributeError: cls.__instance = new (cls, ibase) return cls.__instance class StandardMathematicsSystem(MathematicsSystem): def __init__(self, ibase): if ibase.getBase() != new (IntegralNumber, 2): raise NotImplementedError self.base = ibase.getBase() def calculateFactorial(self, target): result = new (IntegralNumber, 1) i = new (IntegralNumber, 2) while i <= target: result = result * i i = i + new (IntegralNumber, 1) return result print StandardMathematicsSystem.getInstance(new (InternalBase,new (IntegralNumber, 2))).calculateFactorial(new (IntegralNumber, 6))[英文原文：The Evolution of a Python Programmer ]