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How to check if all elements of a list matches a condition?
...ne this with a generator expression to produce the result you want cleanly and efficiently. For example:
>>> items = [[1, 2, 0], [1, 2, 0], [1, 2, 0]]
>>> all(flag == 0 for (_, _, flag) in items)
True
>>> items = [[1, 2, 0], [1, 2, 1], [1, 2, 0]]
>>> all(flag == ...
In a PHP project, what patterns exist to store, access and organize helper objects? [closed]
How do you organize and manage your helper objects like the database engine, user notification, error handling and so on in a PHP based, object oriented project?
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Difference between ApiController and Controller in ASP.NET MVC
I've been playing around with ASP.NET MVC 4 beta and I see two types of controllers now: ApiController and Controller .
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What does it mean when MySQL is in the state “Sending data”?
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This is quite a misleading status. It should be called "reading and filtering data".
This means that MySQL has some data stored on the disk (or in memory) which is yet to be read and sent over. It may be the table itself, an index, a temporary table, a sorted output etc.
If you have a 1...
Why does make think the target is up to date?
...ve a file/directory named test in the directory. If this directory exists, and has no dependencies that are more recent, then this target is not rebuild.
To force rebuild on these kind of not-file-related targets, you should make them phony as follows:
.PHONY: all test clean
Note that you can de...
Where does R store packages?
...all.packages() function in R is the automatic unzipping utility that gets and install packages in R.
4 Answers
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Are memory leaks ever ok? [closed]
...ever OK to do this?" but rather "Is there ever a good reason to do this?" And "hunting down that memory leak is a pain" isn't a good reason.
I like to keep things simple. And the simple rule is that my program should have no memory leaks.
That makes my life simple, too. If I detect a memory lea...
Why does Typescript use the keyword “export” to make classes and interfaces public?
...meClass = SomeClass;.
So conceptually, visibility as controlled by public and private is just for tooling, whereas the export keyword changes the output.
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MySQL: Set user variable from result of query
...rator. However inside other statements, the assignment operator must be := and not = because = is treated as a comparison operator in non-SET statements.
UPDATE:
Further to comments below, you may also do the following:
SET @user := 123456;
SELECT `group` FROM user LIMIT 1 INTO @group;
SELECT ...
How to link to specific line number on github
...ink to the right lines:
Click on the line number you want (like line 18), and the URL in your browser will get a #L18 tacked onto the end. You literally click on the 18 at the left side, not the line of code. Looks like this:
And now your browser's URL looks like this:
https://github.com/git/gi...