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What is Weak Head Normal Form?
... further (i.e. it contains no un-evaluated thunks).
These expressions are all in normal form:
42
(2, "hello")
\x -> (x + 1)
These expressions are not in normal form:
1 + 2 -- we could evaluate this to 3
(\x -> x + 1) 2 -- we could apply the function
"he" ++ "llo" ...
How do you query for “is not null” in Mongo?
...
This will return all documents with a key called "IMAGE URL", but they may still have a null value.
db.mycollection.find({"IMAGE URL":{$exists:true}});
This will return all documents with both a key called "IMAGE URL" and a non-null value.
d...
How do I grant myself admin access to a local SQL Server instance?
I installed SQL Server 2008 R2 to my local machine. But, I can't create a new database because of rights (or lack of).
6 An...
Convert an image (selected by path) to base64 string
...e to retrieve the base64 string
public static string ImageToBase64(string _imagePath)
{
string _base64String = null;
using (System.Drawing.Image _image = System.Drawing.Image.FromFile(_imagePath))
{
using (MemoryStream _mStream = new MemoryStream())
...
How to install JSTL? The absolute uri: http://java.sun.com/jstl/core cannot be resolved
... deployed with this application
That URI is for JSTL 1.0, but you're actually using JSTL 1.2 which uses URIs with an additional /jsp path (because JSTL, who invented EL expressions, was since version 1.1 integrated as part of JSP in order to share/reuse the EL logic in plain JSP too).
So, fix the...
How to Update Multiple Array Elements in mongodb
...At this moment it is not possible to use the positional operator to update all items in an array. See JIRA http://jira.mongodb.org/browse/SERVER-1243
As a work around you can:
Update each item individually
(events.0.handled events.1.handled
...) or...
Read the document, do the edits
manually and ...
How do you share code between projects/solutions in Visual Studio?
...sulting in multiple assemblies: however, when coupled with ILMerge - especially with the internalize option - it becomes a very powerful solution.
– user2246674
Jun 28 '13 at 5:27
...
error LNK2019: 无法解析的外部符号 _Netbios@4,该符号在函数 中被引用 - C...
error LNK2019: 无法解析的外部符号 _Netbios@4,该符号在函数 中被引用解决方法如下：Cpp文件include语句之后加上如下代码：#pragma comment(lib,"netapi32.lib")解决方法如下：
Cpp文件include语句之后加上如下代码：
#pragma comment(lib,"netapi32.lib")
...
如何把一个POINT转化为lParam参数 - C/C++ - 清泛网 - 专注C/C++及内核技术
...ARAM(pt.x, pt.y);反之：CPoint point(lParam);里面的实现是：CPoint(_In_ LPARAM dwPoint) throw();...ATLTYPES_INLINE CPoin...MAKELPARAM(pt.x, pt.y);
反之：
CPoint point(lParam);
里面的实现是：
CPoint(_In_ LPARAM dwPoint) throw();
...
ATLTYPES_INLINE CPoint::CPoint(_In...
How do I create a MongoDB dump of my database?
...ump:
$ ./mongodump --host prod.example.com
connected to: prod.example.com
all dbs
DATABASE: log to dump/log
log.errors to dump/log/errors.bson
713 objects
log.analytics to dump/log/analytics.bson
234810 objects
DATABASE: blog to dump/blog
...