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Is null reference possible?
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References are not pointers.
8.3.2/1:
A reference shall be initialized to
refer to a valid object or function.
[Note: in particular, a null reference
cannot exist in a well-defined
program, because the only way to
create such a reference would be to
bind it to the ...
How do I list loaded plugins in Vim?
...
Not a VIM user myself, so forgive me if this is totally offbase. But according to what I gather from the following VIM Tips site:
" where was an option set
:scriptnames : list all plugins, _vimrcs loaded (super)
:verbose set history? : reveals value of hist...
用App Inventor 2做扫描仪App？从拍照到展示，手把手教你搭一套完整相机功...
...位址赋值给Image1.图片
核心积木拼法如下：
当 按钮_拍照.被点击 执行
调用 Camera1.拍照()
当 Camera1.拍摄完成(图像位址) 执行
设 图像_预览.图片 为 图像位址
设 标签_状态.文本 为 "照片已拍...
How to determine if a point is in a 2D triangle? [closed]
...uction, and division is much, much, slower. Numeric issues are also much smaller, due to no division! all calculations are exact. Thanks, Rick
– user252020
Jan 16 '10 at 4:57
4
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How do we control web page caching, across all browsers?
Our investigations have shown us that not all browsers respect the HTTP cache directives in a uniform manner.
29 Answers
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Get item in the list in Scala?
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Use parentheses:
data(2)
But you don't really want to do that with lists very often, since linked lists take time to traverse. If you want to index into a collection, use Vector (immutable) or ArrayBuffer (mutable) or possibly Array (which is just a Java array, exc...
How to convert a SVG to a PNG with ImageMagick?
... to convert it into a PNG, then I get a 16x16 pixel PNG which is way too small:
18 Answers
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How to wait in a batch script? [duplicate]
...ist on your Windows XP box? According to this post: http://malektips.com/xp_dos_0002.html sleep isn't available on Windows XP, and you have to download the Windows 2003 Resource Kit in order to get it.
Chakrit's answer gives you another way to pause, too.
Try running sleep 10 from a command prompt...
Why does the default parameterless constructor go away when you create one with parameters
...ass, I most likely want to be able to instantiate that class. In order to allow that, the compiler must add a parameterless constructor, which will have no effect but to allow instantiation. This means that I don't have to include an empty constructor in my code just to make it work.
If I've defin...
How can I split up a Git commit buried in history?
...D^ to reset to before the commit, but keep your work tree intact.
Incrementally add changes and commit them, making as many commits as desired. add -p can be useful to add only some of the changes in a given file. Use commit -c ORIG_HEAD if you want to re-use the original commit message for a certai...