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Find intersection of two nested lists?
... 3 filter returns an iterable instead of list, so you need to wrap filter calls with list():
c3 = [list(filter(lambda x: x in c1, sublist)) for sublist in c2]
Explanation:
The filter part takes each sublist's item and checks to see if it is in the source list c1.
The list comprehension is exec...
C# Lazy Loaded Automatic Properties
... 4.0 Lazy<T> type to create this pattern
private Lazy<string> _someVariable =new Lazy<string>(SomeClass.IOnlyWantToCallYouOnce);
public string SomeVariable => _someVariable.Value;
This code will lazily calculate the value of _someVariable the first time the Value expression i...
Facebook Android Generate Key Hash
... answered Mar 15 '11 at 0:02
allthenutsandboltsallthenutsandbolts
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How to split a string and assign it to variables
...
I like Go but I wouldn't call this flexible :D
– Pijusn
May 25 '17 at 4:27
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Web API 最佳入门指南 - 更多技术 - 清泛网 - 专注C/C++及内核技术
...blic class ContactRepository : IContactRepository
{
MongoServer _server = null;
MongoDatabase _database = null;
MongoCollection _contacts = null;
public ContactRepository(string connection)
{
if (string.IsNullOrWhiteSpace(connection))
...
How to Create Multiple Where Clause Query Using Laravel Eloquent?
... '<>', 'value_2'],
[COLUMN, OPERATOR, VALUE],
...
])
Personally I haven't found use-case for this over just multiple where calls, but fact is you can use it.
Since June 2014 you can pass an array to where
As long as you want all the wheres use and operator, you can group them this ...
Why should I prefer to use member initialization lists?
...tyle. For class members which are classes, then it avoids an unnecessary call to a default constructor. Consider:
class A
{
public:
A() { x = 0; }
A(int x_) { x = x_; }
int x;
};
class B
{
public:
B()
{
a.x = 3;
}
private:
A a;
};
In this case, the construct...
'Microsoft.ACE.OLEDB.12.0' provider is not registered on the local machine
...
Well, you need to install it. You're looking for:
The 2007 Office System Driver: Data Connectivity Components.
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OS detecting makefile
... still use solely uname, but you have to deal with if/else blocks to check all MinGW, Cygwin, etc. variations.
The environment variable OS is always set to "Windows_NT" on different Windows versions (see %OS% environment variable on Wikipedia).
An alternative of OS is the environment variable MSVC (...
How to get the sizes of the tables of a MySQL database?
I can run this query to get the sizes of all tables in a MySQL database:
16 Answers
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