'url' requires a non-empty first argument. The syntax changed in Django 1.5, see the docs

Django运行时出现'url' requires a non-empty first argument的解决办法:

参考了stackoverflow里面的一个帖子

I started using Django release 1.5 and got a problem with my old code:
`post`.`title`Error: 'url' requires a non-empty first argument. The syntax changed in Django 1.5, see the docs. Docs:One deprecated feature worth noting is the shift to "new-style" url tag. Prior to Django 1.3, syntax like {% url myview %} was interpreted incorrectly (Django considered "myview" to be a literal name of a view, not a template variable named myview). Django 1.3 and above introduced the {% load url from future %} syntax to bring in the corrected behavior where myview was seen as a variable.The upshot of this is that if you are not using {% load url from future %} in your templates, you'll need to change tags like {% url myview %} to {% url "myview" %}. If you were using {% load url from future %} you can simply remove that line under Django 1.5#该代码片段来自于: http://www.sharejs.com/codes/python/7007

大概意思就是说：原来写成：{%url myview%} 这样的语句在1.5以前的版本是可以通过的，
更换到1.5的版本以后要写成：{%url "myview"%}

经过测试的确如此。