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Swift: Testing optionals for nil
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For those who are new to swift as I am and are wondering: You still have to unwrap xyz inside the if block. It's safe though, even if you force unwrap
– Omar
Jun 10 '19 at 1:05
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Creating a comma separated list from IList or IEnumerable
...ll string.Join. Of course, you don't have to use a helper method:
// C# 3 and .NET 3.5 way:
string joined = string.Join(",", strings.ToArray());
// C# 2 and .NET 2.0 way:
string joined = string.Join(",", new List<string>(strings).ToArray());
The latter is a bit of a mouthful though :)
This...
How to Pass Parameters to Activator.CreateInstance()
...ects using pre compiled lambda. Of course always performance is subjective and it clearly depends on each case if it's worth it or not.
Details about the issue on this article.
Graph is taken from the article and represents time taken in ms per 1000 calls.
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Give all the permissions to a user on a DB
...ng it an admin.
The reason why I want to do that is that at the moment DEV and PROD are different DBs on the same cluster so I don't want a user to be able to change production objects but it must be able to change objects on DEV.
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Count how many files in directory PHP
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glob($directory . "*.{jpg,png,gif}",GLOB_BRACE)
the GLOB_BRACE flag expands {a,b,c} to match 'a', 'b', or 'c'
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missing private key in the distribution certificate on keychain
... anywhere. Basically, we have a company developer account (not enterprise) and so in order to submit our app, I requested from our team lead to send me the distribution certificate and create and send me a distribution provisioning profile.
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How do I sort unicode strings alphabetically in Python?
Python sorts by byte value by default, which means é comes after z and other equally funny things. What is the best way to sort alphabetically in Python?
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What is a “Bitmap heap scan” in a query plan?
...ference is that, rather than visiting every disk page, a bitmap index scan ANDs and ORs applicable indexes together, and only visits the disk pages that it needs to.
This is different from an index scan, where the index is visited row by row in order -- meaning a disk page may get visited multiple ...
Getting the caller function name inside another function in Python? [duplicate]
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There are two ways, using sys and inspect modules:
sys._getframe(1).f_code.co_name
inspect.stack()[1][3]
The stack() form is less readable and is implementation dependent since it calls sys._getframe(), see extract from inspect.py:
def stack(context=...
Getting an empty JQuery object
In the following code I set up a change handler on a select box to show and hide some follow up questions based on the value of the selection.
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