| Server IP : 185.88.153.241 / Your IP : 216.73.217.115 Web Server : LiteSpeed System : Linux server312.bertina.biz 3.10.0-962.3.2.lve1.5.88.el7.x86_64 #1 SMP Fri Sep 26 14:06:42 UTC 2025 x86_64 User : ( 1405) PHP Version : 7.0.33 Disable Function : mail, apache_child_terminate, apache_setenv, define_syslog_variables, escapeshellarg, escapeshellcmd, exec, fp, highlight_file, ini_alter, ini_restore, inject_code, mysql_pconnect, openlog, passthru, phpAds_remoteInfo, phpAds_XmlRpc, phpAds_xmlrpcDecode, phpAds_xmlrpcEncode, popen, posix_kill, posix_mkfifo, posix_setpgid, posix_setsid, proc_close, proc_get_status, proc_nice, proc_open, proc_terminate, shell_exec, syslog, system, xmlrpc_entity_decode, show_source,dl,leak,crack_check,crack_closedict,crack_getlastmessage,crack_opendict,symlink,link,escapeshellarg,parse_ini_file, ln, show_source, pclose, parse_perms, mysql_list_dbs,stream_select,mysql_list_dbs,socket_select,socket_create,socket_create_listen,socket_create_pair,socket_listen,socket_accept,socket_bind,socket_strerror,socket_clear_error,socket_close,socket_connect,socket_get_option,socket_getpeername,socket_getsockname,socket_last_error,socket_read,socket_recv,socket_recvfrom,socket_send,socket_sendto,socket_set_block,socket_set_nonblock,socket_set_option,socket_shutdown,socket_write,readlink,pfsockopen,pcntl_exec,pcntl_fork,pcntl_signal,pcntl_waitpid,pcntl_wexitstatus, pcntl_wifexited, pcntl_wifsignaled, pcntl_wifstopped,pcntl_wstopsig,pcntl_wtermsig,fpassthru, posix_access, posix_ctermid, posix_errno, posix_get_last_error, posix_getcwd, posix_getgrnam, posix_getgroups, posix_getlogin, posix_getpgrp, posix_getpwnam, posix_getpwuid, posix_getrlimit, posix_getsid, posix_initgroups, posix_isatty, posix_mknod, posix_setegid, posix_seteuid, posix_strerror, posix_times, posix_ttyname, diskfreespace, disk_free_space, disk_total_space, sys_getloadavg,get_current_user MySQL : OFF | cURL : ON | WGET : ON | Perl : ON | Python : ON | Sudo : OFF | Pkexec : OFF Directory : /lib64/python2.7/Demo/classes/ |
Upload File : |
'''
A class which presents the reverse of a sequence without duplicating it.
From: "Steven D. Majewski" <sdm7g@elvis.med.virginia.edu>
It works on mutable or inmutable sequences.
>>> chars = list(Rev('Hello World!'))
>>> print ''.join(chars)
!dlroW olleH
The .forw is so you can use anonymous sequences in __init__, and still
keep a reference the forward sequence. )
If you give it a non-anonymous mutable sequence, the reverse sequence
will track the updated values. ( but not reassignment! - another
good reason to use anonymous values in creating the sequence to avoid
confusion. Maybe it should be change to copy input sequence to break
the connection completely ? )
>>> nnn = range(3)
>>> rnn = Rev(nnn)
>>> for n in rnn: print n
...
2
1
0
>>> for n in range(4, 6): nnn.append(n) # update nnn
...
>>> for n in rnn: print n # prints reversed updated values
...
5
4
2
1
0
>>> nnn = nnn[1:-1]
>>> nnn
[1, 2, 4]
>>> for n in rnn: print n # prints reversed values of old nnn
...
5
4
2
1
0
#
>>> WH = Rev('Hello World!')
>>> print WH.forw, WH.back
Hello World! !dlroW olleH
>>> nnn = Rev(range(1, 10))
>>> print nnn.forw
[1, 2, 3, 4, 5, 6, 7, 8, 9]
>>> print nnn.back
[9, 8, 7, 6, 5, 4, 3, 2, 1]
>>> rrr = Rev(nnn)
>>> rrr
<1, 2, 3, 4, 5, 6, 7, 8, 9>
'''
class Rev:
def __init__(self, seq):
self.forw = seq
self.back = self
def __len__(self):
return len(self.forw)
def __getitem__(self, j):
return self.forw[-(j + 1)]
def __repr__(self):
seq = self.forw
if isinstance(seq, list):
wrap = '[]'
sep = ', '
elif isinstance(seq, tuple):
wrap = '()'
sep = ', '
elif isinstance(seq, str):
wrap = ''
sep = ''
else:
wrap = '<>'
sep = ', '
outstrs = [str(item) for item in self.back]
return wrap[:1] + sep.join(outstrs) + wrap[-1:]
def _test():
import doctest, Rev
return doctest.testmod(Rev)
if __name__ == "__main__":
_test()