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JavaScript checking for null vs. undefined and difference between == and ===
...heck if a variable is either undefined or null and nothing else:
function test(val) {
return val == null;
}
test(null); # => true
test(undefined); # => true
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What does the “assert” keyword do? [duplicate]
...
Using assert to test a non public method's precondition is perfectly valid IMO.
– Pascal Thivent
Jun 10 '10 at 22:28
...
using gitlab token to clone without authentication
... of tokens:
Private token
Personal Access Token
CI/CD running token
I tested only the Personal Access Token using GitLab Community Edition 10.1.2, the example:
git clone https://gitlab-ci-token:${Personal Access Tokens}@gitlab.com/username/myrepo.git
git clone https://oauth2:${Personal Acces...
How to store int[] array in application Settings
... to select it by default.
So, create a setting with desired name (e.g. SomeTestSetting) and make it of any type (e.g. string by default).
Save the changes.
Now go to your project folder and open the "Properties\Settings.settings" file with text editor (Notepad, for example) Or you can open it in VS...
Loop through a Map with JSTL [duplicate]
...List list = new ArrayList();
TreeMap itemList=new TreeMap();
itemList.put("test", "test");
list.add(itemList);
pageContext.setAttribute("itemList", list);
%>
<c:forEach items="${itemList}" var="itemrow">
<input type="text" value="<c:out value='${ite...
How to filter array in subdocument with MongoDB [duplicate]
...er individual elements and then use $group to put it back together:
db.test.aggregate([
{ $match: {_id: ObjectId("512e28984815cbfcb21646a7")}},
{ $unwind: '$list'},
{ $match: {'list.a': {$gt: 3}}},
{ $group: {_id: '$_id', list: {$push: '$list.a'}}}
])
outputs:
{
"result": [
...
C++模板-继承-具现化 - C/C++ - 清泛网 - 专注C/C++及内核技术
...pename T>
new_handler NewHandlerSurpport<T>::currentHandler = 0;
class Test : public NewHandlerSurpport<Test>
{
public:
int val;
};
怎么样？看了上面的代码，大家是否有些迷惑？首先，类NewHandlerSurpport采用的模板类的定义，其内部却没用到类型T；其...
Boost智能指针——shared_ptr - C/C++ - 清泛网 - 专注C/C++及内核技术
...}
void do_something() { std::cout << "did something\n"; }
};
void test()
{
boost::shared_ptr<implementation> sp1(new implementation());
std::cout<<"The Sample now has "<<sp1.use_count()<<" references\n";
boost::shared_ptr<implementation> sp2 = sp1;
std::cout<<"The Sam...
AfxIsValidAddress 测试内存地址 - C/C++ - 清泛网 - 专注C/C++及内核技术
AfxIsValidAddress 测试内存地址Tests any memory address to ensure that it is contained entirely within the program& 39;s memory space 测试任何内存 Tests any memory address to ensure that it is contained entirely within the program's memory space.
测试任何内存地址,以确保它...
CFileDialog用法及参数解释 - C/C++ - 清泛网 - 专注C/C++及内核技术
...athName( ) 得到完整的文件名，包括目录名和扩展名如：c:\ test\test1.txt
CString CFileDialog::GetFileName( ) 得到完整的文件名，包括扩展名如：test1.txt
CString CFileDialog::GetFileExt( ) 得到完整的文件扩展名，如：txt
CString CFileDialog::GetFileTitl...