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Batch files - number of command line arguments
... handle number of arguments with this sort of logic:
IF "%1"=="" GOTO HAVE_0
IF "%2"=="" GOTO HAVE_1
IF "%3"=="" GOTO HAVE_2
etc.
If you have more than 9 arguments then you are screwed with this approach though. There are various hacks for creating counters which you can find here, but be warne...
'printf' vs. 'cout' in C++
...in practice with printf is const char * (C string, can be obtained using to_c method of std::string)). For instance, to print size_t, you need to use %zd, while int64_t will require using %"PRId64". The tables are available at http://en.cppreference.com/w/cpp/io/c/fprintf and http://en.cppreference....
How to decorate a class?
...r specific scenario, YMMV :-)
What you're thinking of is a metaclass. The __new__ function in a metaclass is passed the full proposed definition of the class, which it can then rewrite before the class is created. You can, at that time, sub out the constructor for a new one.
Example:
def substitu...
No generic implementation of OrderedDictionary?
... private KeyedCollection2<TKey, KeyValuePair<TKey, TValue>> _keyedCollection;
/// <summary>
/// Gets or sets the value associated with the specified key.
/// </summary>
/// <param name="key">The key associated with the value to get or...
MDI CDockablePane使用总结 - C/C++ - 清泛网 - 专注C/C++及内核技术
...架类的头文件中定义一个CDockablePane的数组
CDockablePane m_Panes[5];//一个CDockablePane的数组
2. CFrameWndEx:: OnCreate() 在Create函数中自动生成了以下代码，对MFC比较熟悉的这里就不讲了：
CMFCPopupMenu::SetForceMenuFocus(FALSE);
InitUserToolbars(N...
Get the client IP address using PHP [duplicate]
...ant to get the client IP address who uses my website. I am using the PHP $_SERVER superglobal:
5 Answers
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How to find the JVM version from a program?
...version "12" "1.8.0_201" "1.5.0_22" Java Runtime Environment version, which may be interpreted as a Runtime.Version
java.version.date "2019-03-19" ...
How to select a single field for all documents in a MongoDB collection?
...uery. In the result set, only the item and qty fields and, by default, the _id field return in the matching documents.
db.inventory.find( { type: 'food' }, { item: 1, qty: 1 } )
In this example from the folks at Mongo, the returned documents will contain only the fields of item, qty, and _id.
Thus...
How to deal with SettingWithCopyWarning in Pandas?
...H5390 and GH5597 for background discussion.]
df[df['A'] > 2]['B'] = new_val # new_val not set in df
The warning offers a suggestion to rewrite as follows:
df.loc[df['A'] > 2, 'B'] = new_val
However, this doesn't fit your usage, which is equivalent to:
df = df[df['A'] > 2]
df['B'] = ...
What is the __del__ method, How to call it?
I am reading a code. There is a class in which __del__ method is defined. I figured out that this method is used to destroy an instance of the class. However, I cannot find a place where this method is used. The main reason for that is that I do not know how this method is used, probably not like ...