21.2-习题命令分发器、copy和单词统计

真正成熟的人，首先应该是一个懂得克制自己欲望的人。
克制，其实是一种更高级的自律。

所谓“美女都是狠角色”，不是没有道理的。

就我身边的大多数美女而言，她们可以克制住自己不胡吃海喝、不沾辛辣、不熬夜，在别人偷懒的时候，她们坚持运动，每天敷面膜、保养皮肤。

“学霸”也不是不食人间烟火，更不是没有七情六欲，他们不过是比常人更懂得克制自己。

我认识的一位学霸，大学那么多年都觉得他除了学习，简直无欲无求。

谁知等他拿到了心仪企业的offer和研究生的录取通知后，一口气做了两件大事：脱单+一个月的长途旅行。

真正成熟的人，知道自己想要的是什么，更知道自己什么时候该做什么事情，懂得克制自己。

在别人都在玩的时候，努力克制。等拥有了足够的选择权之后，再去放肆。

完善命令分发器，实现函数可以带任意参数（可变参数除外），解析参数并要求用户输入
即解决下面的问题;

思路：可以有2种方式

1、注册的时候，固定死，@reg('py',200,100)
可以认为@reg('py',200,100)和@reg('py',300,100)是不同的函数，可以用partial函数。
2、运行时，在输入cmd的时候，逗号或空格分割，获取参数。
至于函数的验证，以后实现。
一般用户都喜欢使用单纯一个命令如mag，然后直接显示想要的结果，所以采用第一种方式

from functools import partial

def command_dispatcher(defaultfn=lambda :print('Unknown command')):
    # 构建全局字典
    cmd_tb1 = {}
    
    #注册函数
    def reg(cmd,*args,**kwargs):
        def _reg(fn):
            func = partial(fn,*args,**kwargs)
            commands[cmd] = func
            return func
        return _reg

    def default_func():
        print("Unknown command")

    def dispatcher():
        while True:
            cmd = input('>>>').strip()
            # 退出条件
            if cmd == '':
                print('bye')
                return
            cmd_tb1.get(cmd, default_func)()
            
    return reg,dispatcher
        
reg, dispatcher = command_dispatcher()
        
@reg('mag',z=200,y=300,x=100)
@reg('mag1',z=300,y=300,x=300)
def foo1(x,y,z):
    print('magedu',x,y,z)
   
@reg('py',300,b=400)
def foo2(a,b=100):
    print('python',a,b)
#reg('mag', foo1)
#reg('py', foo2)

dispatcher()

练习1： copy文件内容

复制tmp目录下文件1里面的内容到一个新文本中；

filename1 = './tmp/test.txt'
filename2 = './tmp/test1.txt'

f = open(filename1,'w+')
lines = ['abc','123','magedu']
f.writelines('\n'.join(lines))

f.seek(0)
print(f.read())
f.close()

def copy(src,dest):
    with open(src) as f1:
        with open(dest,'w') as f2:
            f2.write(f1.read())
            
copy(filename1,filename2)
----------------------------------------------------------------
abc
123
magedu

总结：
1.只要是文件操作，能用 with 就用 with ；看见open，就想一想要不要用with;

练习2： 单词统计

# 缺省字典
from collections import defaultdict
filename = './sample.txt'
count = 0
d = defaultdict(lambda:0)   # 缺省字典判断
with open(filename,encoding='utf8') as f:
    for line in f:
        print(line)
        count += 1
        #if count == 5:break
            
        words = line.split()
        for word in words:
            d[word] += 1
            
print(sorted(d.items(),key=lambda x: x[1],reverse=True))
----------------------------------------------------------------------------------
[('the', 124), ('is', 60), ('a', 54), ('path', 52), ('and', 39), ('of', 33), ('if', 32), ('to', 31), ('or', 24), ('Return', 22), ('in', 20), ('an', 18), ('on', 17), ('file', 17), ('for', 16), ('pathname', 15), ('not', 15), ('On', 15), ('be', 14), ('that', 14), ('path.', 14), ('drive', 14), ('are', 13), ('by', 13), ('True', 13), ('The', 12), ('as', 12), ('same', 12), ('all', 11), ('will', 11), ('Windows', 10), ('This', 10), ('returns', 10), ('If', 10), ('it', 10), ('Python', 9), ('version', 9), ('function', 9), ('directory', 9), ('»', 8), ('Unix,', 8), ('paths', 8), ('return', 8), ('symbolic', 8), ('Windows,', 8), ('number', 8), ('can', 7), ('different', 7), ('this', 7), ('from', 7), ('with', 7), ('time', 7), ('|', 6), ('module', 6), ('names', 6), ('may', 6), ('does', 6), ('empty', 6), ('Raise', 6), ('contains', 6), ('Availability:', 6), ('path,', 6), ('component', 6), ('last', 6), ('point', 6), ('mount', 6), ('Windows.', 6), ('see', 5), ('either', 5), ('so', 5), ('Unix', 5), ('use', 5), ('string', 5), ('Note', 5), ('result', 5), ('name', 5), ('always', 5), ('pair', 5), ('returned', 5), ('both', 5), ('absolute', 5), ('empty.', 5), ('Changed', 5), ('directory.', 5), ('up', 5), ('value', 5), ('since', 5), ('into', 5), ('tail', 5), ('previous', 4), ('some', 4), ('objects', 4), ('any', 4), ('also', 4), ('one', 4), ('where', 4), ('relative', 4), ('existing', 4), ('False', 4), ('initial', 4), ('current', 4), ('OSError', 4), ('exist', 4), ('inaccessible.', 4), ('slashes', 4), ('Split', 4), ('head', 4), ('modules', 3), ('(for', 3), ('functions', 3), ('To', 3), ('represent', 3), ('strings', 3), ('should', 3), ('bytes', 3), ('only', 3), ('operating', 3), ('systems', 3), ('have', 3), ('there', 3), ('system', 3), ('basename', 3), ('each', 3), ('refers', 3), ('links.', 3), ('~user', 3), ('replaced', 3), ('environment', 3), ('variable', 3), ('used', 3), ('supported', 3), ('giving', 3), ('seconds', 3), ('epoch', 3), ('(see', 3), ('module).', 3), ('begins', 3), ('file.', 3), ('device', 3), ('letter', 3), ('root', 3), ('UNC', 3), ('3.4:', 3), ('components', 3), ('part', 3), ('converts', 3), ('refer', 3), ('Added', 3), ('support.', 3), ('tail)', 3), ('contain', 3), ('string.', 3), ('Navigation', 2), ('index', 2), ('next', 2), ('3.5.3', 2), ('Documentation', 2), ('Standard', 2), ('Library', 2), ('11.', 2), ('File', 2), ('Directory', 2), ('Access', 2), ('os.path', 2), ('—', 2), ('implements', 2), ('filesystem', 2), ('bytes.', 2), ('character', 2), ('applications', 2), ('arbitrary', 2), ('using', 2), ('standard', 2), ('access', 2), ('Unlike', 2), ('do', 2), ('such', 2), ('when', 2), ('paths.', 2), ('you', 2), ('most', 2), ('platforms,', 2), ('element', 2), ('passing', 2), ('split().', 2), ("('').", 2), ('longest', 2), ('valid', 2), ('New', 2), ('prefix', 2), ('empty,', 2), ('at', 2), ('>>>', 2), ("'/usr/local/lib'])", 2), ('open', 2), ('Returns', 2), ('broken', 2), ('os.stat()', 2), ('now', 2), ('argument', 2), ('~', 2), ('home', 2), ('HOME', 2), ('otherwise', 2), ('looked', 2), ('password', 2), ('An', 2), ('unchanged.', 2), ('variables', 2), ('$name', 2), ('references', 2), ('os.stat_float_times()', 2), ('True,', 2), ('floating', 2), ('number.', 2), ('(like', 2), ('pathname.', 2), ('slash,', 2), ('follows', 2), ('links,', 2), ('islink()', 2), ('true', 2), ('links', 2), ('been', 2), ('whether', 2), ('i-node', 2), ('points', 2), ('other', 2), ('more', 2), ('separator', 2), ('meaning', 2), ('thrown', 2), ('away', 2), ('letter,', 2), ('Normalize', 2), ('forward', 2), ('backward', 2), ('slashes.', 2), ('system).', 2), ('start', 2), ('3.2:', 2), ('everything', 2), ('In', 2), ('cases,', 2), ('+', 2), ('including', 2), ('e.g.', 2), ('"/dir")', 2), ('ext', 2), ('unc', 2), ('(such', 2), ('rest', 2), ('Software', 2), ('11.2.', 1), ('Common', 1), ('manipulations', 1), ('Source', 1), ('code:', 1), ('Lib/posixpath.py', 1), ('POSIX),', 1), ('Lib/ntpath.py', 1), ('NT),', 1), ('Lib/macpath.py', 1), ('Macintosh)', 1), ('--------------------------------------------------------------------------------', 1), ('useful', 1), ('pathnames.', 1), ('read', 1), ('write', 1), ('files', 1), ('open(),', 1), ('accessing', 1), ('os', 1), ('module.', 1), ('parameters', 1), ('passed', 1), ('strings,', 1), ('Applications', 1), ('encouraged', 1), ('(Unicode)', 1), ('strings.', 1), ('Unfortunately,', 1), ('representable', 1), ('need', 1), ('support', 1), ('names.', 1), ('Vice', 1), ('versa,', 1), ('cannot', 1), ('(in', 1), ('mbcs', 1), ('encoding),', 1), ('hence', 1), ('files.', 1), ('unix', 1), ('shell,', 1), ('automatic', 1), ('expansions.', 1), ('Functions', 1), ('expanduser()', 1), ('expandvars()', 1), ('invoked', 1), ('explicitly', 1), ('application', 1), ('desires', 1), ('shell-like', 1), ('expansion.', 1), ('(See', 1), ('glob', 1), ('module.)', 1), ('See', 1), ('pathlib', 1), ('offers', 1), ('high-level', 1), ('objects.', 1), ('All', 1), ('these', 1), ('accept', 1), ('their', 1), ('parameters.', 1), ('object', 1), ('type,', 1), ('returned.', 1), ('Since', 1), ('conventions,', 1), ('several', 1), ('versions', 1), ('library.', 1), ('suitable', 1), ('running', 1), ('on,', 1), ('therefore', 1), ('usable', 1), ('local', 1), ('However,', 1), ('import', 1), ('individual', 1), ('want', 1), ('manipulate', 1), ('formats.', 1), ('They', 1), ('interface:', 1), ('posixpath', 1), ('UNIX-style', 1), ('ntpath', 1), ('macpath', 1), ('old-style', 1), ('MacOS', 1), ('os.path.abspath(path)', 1), ('normalized', 1), ('absolutized', 1), ('equivalent', 1), ('calling', 1), ('normpath()', 1), ('follows:', 1), ('normpath(join(os.getcwd(),', 1), ('path)).', 1), ('os.path.basename(path)', 1), ('base', 1), ('second', 1), ('program;', 1), ("'/foo/bar/'", 1), ("'bar',", 1), ('basename()', 1), ('os.path.commonpath(paths)', 1), ('common', 1), ('sub-path', 1), ('sequence', 1), ('ValueError', 1), ('pathnames,', 1), ('commonprefix(),', 1), ('3.5.', 1), ('os.path.commonprefix(list)', 1), ('(taken', 1), ('character-by-character)', 1), ('list.', 1), ('list', 1), ('invalid', 1), ('because', 1), ('works', 1), ('time.', 1), ('obtain', 1), ('commonpath().', 1), ("os.path.commonprefix(['/usr/lib',", 1), ("'/usr/l'", 1), ("os.path.commonpath(['/usr/lib',", 1), ("'/usr'", 1), ('os.path.dirname(path)', 1), ('first', 1), ('os.path.exists(path)', 1), ('descriptor.', 1), ('permission', 1), ('granted', 1), ('execute', 1), ('requested', 1), ('file,', 1), ('even', 1), ('physically', 1), ('exists.', 1), ('3.3:', 1), ('integer:', 1), ('descriptor,', 1), ('otherwise.', 1), ('os.path.lexists(path)', 1), ('Equivalent', 1), ('exists()', 1), ('platforms', 1), ('lacking', 1), ('os.lstat().', 1), ('os.path.expanduser(path)', 1), ('user‘s', 1), ('set;', 1), ('user’s', 1), ('through', 1), ('built-in', 1), ('pwd.', 1), ('directly', 1), ('USERPROFILE', 1), ('set,', 1), ('combination', 1), ('HOMEPATH', 1), ('HOMEDRIVE', 1), ('used.', 1), ('handled', 1), ('stripping', 1), ('created', 1), ('user', 1), ('derived', 1), ('above.', 1), ('expansion', 1), ('fails', 1), ('begin', 1), ('tilde,', 1), ('os.path.expandvars(path)', 1), ('expanded.', 1), ('Substrings', 1), ('form', 1), ('${name}', 1), ('name.', 1), ('Malformed', 1), ('non-existing', 1), ('left', 1), ('%name%', 1), ('expansions', 1), ('addition', 1), ('${name}.', 1), ('os.path.getatime(path)', 1), ('os.path.getmtime(path)', 1), ('modification', 1), ('os.path.getctime(path)', 1), ('system’s', 1), ('ctime', 1), ('which,', 1), ('Unix)', 1), ('metadata', 1), ('change,', 1), ('and,', 1), ('others', 1), ('Windows),', 1), ('creation', 1), ('os.path.getsize(path)', 1), ('size,', 1), ('bytes,', 1), ('os.path.isabs(path)', 1), ('means', 1), ('(back)slash', 1), ('after', 1), ('chopping', 1), ('off', 1), ('potential', 1), ('letter.', 1), ('os.path.isfile(path)', 1), ('regular', 1), ('isfile()', 1), ('os.path.isdir(path)', 1), ('isdir()', 1), ('os.path.islink(path)', 1), ('entry', 1), ('link.', 1), ('Always', 1), ('runtime.', 1), ('os.path.ismount(path)', 1), ('point:', 1), ('has', 1), ('mounted.', 1), ('POSIX,', 1), ('checks', 1), ('path‘s', 1), ('parent,', 1), ('path/..,', 1), ('than', 1), ('path/..', 1), ('detect', 1), ('POSIX', 1), ('variants.', 1), ('share', 1), ('points,', 1), ('GetVolumePathName', 1), ('called', 1), ('input', 1), ('Support', 1), ('detecting', 1), ('non-root', 1), ('os.path.join(path,', 1), ('*paths)', 1), ('Join', 1), ('intelligently.', 1), ('concatenation', 1), ('members', 1), ('*paths', 1), ('exactly', 1), ('(os.sep)', 1), ('following', 1), ('non-empty', 1), ('except', 1), ('last,', 1), ('end', 1), ('joining', 1), ('continues', 1), ('component.', 1), ('reset', 1), ('(e.g.,', 1), ("r'\\foo')", 1), ('encountered.', 1), ('reset.', 1), ('drive,', 1), ('os.path.join("c:",', 1), ('"foo")', 1), ('represents', 1), ('C:', 1), ('(c:foo),', 1), ('c:\\foo.', 1), ('os.path.normcase(path)', 1), ('case', 1), ('Mac', 1), ('OS', 1), ('X,', 1), ('unchanged;', 1), ('case-insensitive', 1), ('filesystems,', 1), ('lowercase.', 1), ('TypeError', 1), ('type', 1), ('str', 1), ('os.path.normpath(path)', 1), ('collapsing', 1), ('redundant', 1), ('separators', 1), ('up-level', 1), ('A//B,', 1), ('A/B/,', 1), ('A/./B', 1), ('A/foo/../B', 1), ('become', 1), ('A/B.', 1), ('manipulation', 1), ('change', 1), ('normalize', 1), ('case,', 1), ('normcase().', 1), ('os.path.realpath(path)', 1), ('canonical', 1), ('specified', 1), ('filename,', 1), ('eliminating', 1), ('encountered', 1), ('(if', 1), ('they', 1), ('os.path.relpath(path,', 1), ('start=os.curdir)', 1), ('filepath', 1), ('optional', 1), ('computation:', 1), ('accessed', 1), ('confirm', 1), ('existence', 1), ('nature', 1), ('start.', 1), ('defaults', 1), ('os.curdir.', 1), ('os.path.samefile(path1,', 1), ('path2)', 1), ('arguments', 1), ('determined', 1), ('raises', 1), ('exception', 1), ('call', 1), ('fails.', 1), ('uses', 1), ('implementation', 1), ('platforms.', 1), ('os.path.sameopenfile(fp1,', 1), ('fp2)', 1), ('descriptors', 1), ('fp1', 1), ('fp2', 1), ('os.path.samestat(stat1,', 1), ('stat2)', 1), ('stat', 1), ('tuples', 1), ('stat1', 1), ('stat2', 1), ('These', 1), ('structures', 1), ('os.fstat(),', 1), ('os.lstat(),', 1), ('os.stat().', 1), ('underlying', 1), ('comparison', 1), ('samefile()', 1), ('sameopenfile().', 1), ('os.path.split(path)', 1), ('pair,', 1), ('(head,', 1), ('leading', 1), ('that.', 1), ('never', 1), ('slash;', 1), ('ends', 1), ('no', 1), ('slash', 1), ('Trailing', 1), ('stripped', 1), ('unless', 1), ('(one', 1), ('only).', 1), ('join(head,', 1), ('location', 1), ('(but', 1), ('differ).', 1), ('Also', 1), ('dirname()', 1), ('basename().', 1), ('os.path.splitdrive(path)', 1), ('(drive,', 1), ('which', 1), ('specifications,', 1), ('splits', 1), ('drive/UNC', 1), ('sharepoint', 1), ('colon.', 1), ('splitdrive("c:/dir")', 1), ('("c:",', 1), ('host', 1), ('share,', 1), ('but', 1), ('fourth', 1), ('separator.', 1), ('splitdrive("//host/computer/dir")', 1), ('("//host/computer",', 1), ('os.path.splitext(path)', 1), ('(root,', 1), ('ext)', 1), ('==', 1), ('period', 1), ('period.', 1), ('Leading', 1), ('periods', 1), ('ignored;', 1), ("splitext('.cshrc')", 1), ("('.cshrc',", 1), ("'').", 1), ('os.path.splitunc(path)', 1), ('Deprecated', 1), ('3.1:', 1), ('Use', 1), ('splitdrive', 1), ('instead.', 1), ('(unc,', 1), ('rest)', 1), ("r'\\\\host\\mount'),", 1), ('present,', 1), ("r'\\path\\file.ext').", 1), ('For', 1), ('containing', 1), ('letters,', 1), ('os.path.supports_unicode_filenames', 1), ('Unicode', 1), ('(within', 1), ('limitations', 1), ('imposed', 1), ('©', 1), ('Copyright', 1), ('2001-2017,', 1), ('Foundation.', 1), ('Foundation', 1), ('non-profit', 1), ('corporation.', 1), ('Please', 1), ('donate.', 1), ('Last', 1), ('updated', 1), ('Jan', 1), ('16,', 1), ('2017.', 1), ('Found', 1), ('bug?', 1), ('Created', 1), ('Sphinx', 1), ('1.3.1.', 1)]

for k in d:
    if k.find('path') > -1:    # 查找不到返回 -1 ，
        print(k)
------------------------------------------------------------
os.path
pathname
Lib/posixpath.py
Lib/ntpath.py
Lib/macpath.py
pathnames.
path
pathlib
paths.
posixpath
paths
ntpath
macpath
os.path.abspath(path)
path.
normpath()
normpath(join(os.getcwd(),
path)).
os.path.basename(path)
os.path.commonpath(paths)
sub-path
...............


# 完整代码；
def makekey(s:str):
    chars = set(r"""!'"#./\()[],*-""")
    key = s.lower()
    ret = []
    for i, c in enumerate(key):
        if c in chars:
            ret.append(' ')
        else:
            ret.append(c)
    return ''.join(ret).split()

def makekey1(s:str):
    chars = set(r"""!'"#./\()[],*-""")

    key = s.lower()
    ret = []
    start = 0
    for i, c in enumerate(key):
        if c in chars:
            if start == i: # 如果紧挨着还是特殊字符，start一定等于i
                start += 1 # 加1并continue
                continue
            ret.append(key[start:i])
            start = i + 1 # 加1是跳过这个不需要的特殊字符c
    else:
        if start < len(key): # 小于，说明还有有效的字符，而且一直到末尾
            ret.append(key[start:])
            
    return ret

print(makekey('a.b.c'))
print(makekey1('[[[[os.path....join(path,)]]]]'))
#-----------------------------------------------------------------------
['a', 'b', 'c']
['os', 'path', 'join', 'path']


d = {}
with open('./sample.txt', encoding='utf8') as f:
    for line in f:
        words = line.split()
        for wordlist in map(makekey1,words):
            for word in wordlist:
                d[word] = d.get(word,0) + 1

for k,v in sorted(d.items(),key=lambda item: item[1],reverse= True):
    print(k,v)
#--------------------------------------------------
path 138
the 136
is 60
a 59
os 49
if 43
and 40
to 34
on 33
of 33
return 30
windows 25
file 24
or 24
in 24
for 20
an 20
pathname 17
this 17
true 17
drive 17
directory 16
unix 16
not 15
that 15
be 14
by 14
empty 14
3 13
are 13
paths 13