大约有 40,000 项符合查询结果（耗时：0.0443秒） [XML]
How to empty a list?
...
This actually removes the contents from the list, but doesn't replace the old label with a new empty list:
del lst[:]
Here's an example:
lst1 = [1, 2, 3]
lst2 = lst1
del lst1[:]
print(lst2)
For the sake of completeness, the slic...
What do ellipsis […] mean in a list?
... an infinite loop of references, so it decided to cut it short, it's not really infinite. And no, it's not really useful besides a thought experiment :)
– Óscar López
Jun 18 '13 at 3:44
...
How to check Oracle database for long running queries
...ime -- Time since current mode was granted
from
v$locked_object, all_objects, v$lock
where
v$locked_object.object_id = all_objects.object_id AND
v$lock.id1 = all_objects.object_id AND
v$lock.sid = v$locked_object.session_id
order by
session_id, ctime desc, object_name
/
This is a...
Get all unique values in a JavaScript array (remove duplicates)
...l loop through the array and leave only those entries that pass the given callback function onlyUnique.
onlyUnique checks, if the given value is the first occurring. If not, it must be a duplicate and will not be copied.
This solution works without any extra library like jQuery or prototype.js.
It w...
What exactly does @synthesize do?
...then will result in having two ivars, namely someInt plus an autogenerated _someInt variable. Thus self.someInt and someInt will not address the same variables any more. If you don't expect such behavior as I did this might get you some headache to find out.
...
Run a string as a command within a Bash script
...
eval is an evil command in all programming languages so use it with caution.
– Krishnadas PC
Jul 17 '18 at 6:50
1
...
SVN needs-lock 设置强制只读属性（官方资料） - 环境配置 - 清泛IT论坛，...
...when the property is not available
sets the svn:needs-lock property on all already existing binary files in repositories
configures users to automatically set property svn:needs-lock on newly added binary files1) - create a pre-commit.cmd script in the repository\hooks directory. This script...
Save ArrayList to SharedPreferences
...Set the values
Set<String> set = new HashSet<String>();
set.addAll(listOfExistingScores);
scoreEditor.putStringSet("key", set);
scoreEditor.commit();
You can also serialize your ArrayList and then save/read it to/from SharedPreferences. Below is the solution:
EDIT:
Ok, below is the sol...
Why is reading lines from stdin much slower in C++ than Python?
...tl;dr: Because of different default settings in C++ requiring more system calls.
By default, cin is synchronized with stdio, which causes it to avoid any input buffering. If you add this to the top of your main, you should see much better performance:
std::ios_base::sync_with_stdio(false);
Normall...
How to access property of anonymous type in C#?
...null in three different situations!
o is null, so there is no object at all
o is non-null but doesn't have a property Foo
o has a property Foo but its real value happens to be null.
So this is not equivalent to the earlier examples, but may make sense if you want to treat all three cases the sa...