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Is there a Python equivalent of the C# null-coalescing operator?
In C# there's a null-coalescing operator (written as ?? ) that allows for easy (short) null checking during assignment:
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Getting a map() to return a list in Python 3.x
...ases, this ends up saving memory, and should make things go faster.
If all you're going to do is iterate over this list eventually, there's no need to even convert it to a list, because you can still iterate over the map object like so:
# Prints "ABCD"
for ch in map(chr,[65,66,67,68]):
prin...
Quick easy way to migrate SQLite3 to MySQL? [closed]
...y's built a solid library that can convert between the two.
Here a list of ALL the differences in SQL syntax that I know about between the two file formats:
The lines starting with:
BEGIN TRANSACTION
COMMIT
sqlite_sequence
CREATE UNIQUE INDEX
are not used in MySQL
SQLite uses CREATE TABLE/INSERT ...
How to list out all the subviews in a uiviewcontroller in iOS?
I want to list out all the subviews in a UIViewController . I tried self.view.subviews , but not all of the subviews are listed out, for instance, the subviews in the UITableViewCell are not found. Any idea?
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List all files in one directory PHP [duplicate]
What would be the best way to list all the files in one directory with PHP? Is there a $_SERVER function to do this? I would like to list all the files in the usernames/ directory and loop over that result with a link, so that I can just click the hyperlink of the filename to get there. Thanks!
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How do I safely pass objects, especially STL objects, to and from a DLL?
How do I pass class objects, especially STL objects, to and from a C++ DLL?
4 Answers
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MySQL, Check if a column exists in a table with SQL
...pecific column, and if not — create it. Otherwise do nothing. This is really an easy procedure in any enterprise-class database, yet MySQL seems to be an exception.
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How should I call 3 functions in order to execute them one after the other?
If I need call this functions one after other,
11 Answers
11
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How to var_dump variables in twig templates?
... layer pattern where you only present what you have been given is fine and all, but how do you know what is available? Is there a "list all defined variables" functionality in TWIG? Is there a way to dump a variable?
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Can you test google analytics on a localhost address?
...ersal Analytics - analytics.js
Google released a new version of analytics called "Universal Analytics" (late 2012 or early 2013). As I write, this the program is still in BETA so the above code is still recommended for most users with existing installations of Google Analytics.
However, for new deve...