Question

我正在研究python基础知识。我有这样的问题，我无法弄清楚。

views.py

# -*- coding: utf-8 -*-

from django.http import HttpResponse
import datetime

def hello(request):
    return HttpResponse("Hello, World!")

def time(request):
    now = datetime.datetime.now()
    html = "<html><body>Teraz jest %s</body></html>" %now
    return HttpResponse(html)

def time_offset(request, offset):
    delta = int(offset)
    dt = datetime.datetime.now() + datetime.timedelta(hours=offset)
    assert False
    shtml = "<html><body>za %s godzin będzie %s</body></html>" % (delta,dt)
    return HttpResponse(shtml)

urls.py

# -*- coding: utf-8 -*-
from django.conf.urls import patterns, include, url


urlpatterns = patterns('',
    url(r'^hello$', 'mysite.views.hello', name='hello'),
    url(r'^time$', 'mysite.views.time', name='time'),
    url(r'^time\plus\(/d+{1,2})$', 'mysite.views.time_offset', name='time_offset'),   )

这都是我最后一行的网址。我在那里激活我的新观点“time_offset”，一定是它的错误，但我不知道怎么回事？我无法让这种观点发挥作用。

谢谢你的帮助，欢呼！

错误代码：

error at /time/plus/2
multiple repeat
Request Method: GET
Request URL:    http://127.0.0.1:8000/time/plus/2
Django Version: 1.4.5
Exception Type: error
Exception Value:    
multiple repeat
Exception Location: /usr/lib/python2.7/re.py in _compile, line 242
Python Executable:  /usr/bin/python
Python Version: 2.7.3
Python Path:    
['/home/maze/Dokumenty/djcode/mysite',
 '/usr/lib/python2.7',
 '/usr/lib/python2.7/plat-linux2',
 '/usr/lib/python2.7/lib-tk',
 '/usr/lib/python2.7/lib-old',
 '/usr/lib/python2.7/lib-dynload',
 '/usr/local/lib/python2.7/dist-packages',
 '/usr/lib/python2.7/dist-packages',
 '/usr/lib/python2.7/dist-packages/PIL',
 '/usr/lib/python2.7/dist-packages/gtk-2.0',
 '/usr/lib/pymodules/python2.7']
Server time:    Tue, 10 Dec 2013 04:40:17 -0600

Answer 1

正则表达式组合了两个重复修饰符（+，{1, 2}）

>>> re.compile(r'\d+{1,2}')
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "C:\Python27\lib\re.py", line 190, in compile
    return _compile(pattern, flags)
  File "C:\Python27\lib\re.py", line 242, in _compile
    raise error, v # invalid expression
sre_constants.error: multiple repeat

仅使用+或{1,2}：

>>> re.compile(r'\d{1,2}')
<_sre.SRE_Pattern object at 0x00000000025C5458>
>>> re.compile(r'\d+')
<_sre.SRE_Pattern object at 0x0000000002A454F0>

顺便说一句，似乎代码交换了\和/。

... r'^time\plus\(/d+{1,2})$ ...
#          ^    ^ ^

Django / Python“多次重复”

1 个答案: