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Use of “global” keyword in Python
What I understand from reading the documentation is that Python has a separate namespace for functions, and if I want to use a global variable in that function, I need to use global .
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CREATE TABLE IF NOT EXISTS equivalent in SQL Server [duplicate]
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if not exists (select * from sysobjects where name='cars' and xtype='U')
create table cars (
Name varchar(64) not null
)
go
The above will create a table called cars if the table does not already exist.
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What is a C++ delegate?
...is the general idea of a delegate in C++? What are they, how are they used and what are they used for?
6 Answers
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Can you find all classes in a package using reflection?
...quired to tell the VM which classes it can provide, instead they are just handed requests for classes, and have to return a class or throw an exception.
However, if you write your own class loaders, or examine the classpaths and it's jars, it's possible to find this information. This will be via fi...
Why shouldn't all functions be async by default?
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First off, thank you for your kind words. It is indeed an awesome feature and I am glad to have been a small part of it.
If all my code is slowly turning async, why not just make it all async by default?
Well, you're exaggerating; all your code isn't turning async. When you add two "plain" in...
Is it possible to cherry-pick a commit from another git repository?
...ository as a remote, then fetch its changes. From there you see the commit and you can cherry-pick it.
Like that:
git remote add other https://example.link/repository.git
git fetch other
Now you have all the information to simply do git cherry-pick.
More info about working with remotes here: ht...
How do you use String.substringWithRange? (or, how do Ranges work in Swift?)
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You can use the substringWithRange method. It takes a start and end String.Index.
var str = "Hello, playground"
str.substringWithRange(Range<String.Index>(start: str.startIndex, end: str.endIndex)) //"Hello, playground"
To change the start and end index, use advancedBy(n).
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What is the difference between a 'closure' and a 'lambda'?
Could someone explain? I understand the basic concepts behind them but I often see them used interchangeably and I get confused.
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Why is there no String.Empty in Java?
I understand that every time I type the string literal "" , the same String object is referenced in the string pool.
11 An...
How to check if a string contains a substring in Bash
... that spaces in the needle string need to be placed between double quotes, and the * wildcards should be outside. Also note that a simple comparison operator is used (i.e. ==), not the regex operator =~.
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