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How to delete all files and folders in a directory?
...e(true);
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If your directory may have many files, EnumerateFiles() is more efficient than GetFiles(), because when you use EnumerateFiles() you can start enumerating it before the whole collection is returned, as opposed to GetFiles() where you need to load the entire collection in memory befor...
Unable to Cast from Parent Class to Child Class
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The best way to remove duplicate values from NSMutableArray in Objective-C?
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I know this is an old question, but there is a more elegant way to remove duplicates in a NSArray if you don't care about the order.
If we use Object Operators from Key Value Coding we can do this:
uniquearray = [yourarray valueForKeyPath:@"@distinctUnionOfObjects.self"...
Difference between Statement and PreparedStatement
The Prepared Statement is a slightly more powerful version of a Statement, and should always be at least as quick and easy to handle as a Statement.
The Prepared Statement may be parametrized
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How do you clear the SQL Server transaction log?
...example, if you have a business rule that states you can afford to lose no more than 15 minutes of data in the event of a disaster, you should have a job that backs up the log every 15 minutes. Here is a script that will generate timestamped file names based on the current time (but you can also do ...
Are HLists nothing more than a convoluted way of writing tuples?
I am really interested in finding out where the differences are, and more generally, to identify canonical use cases where HLists cannot be used (or rather, don't yield any benefits over regular lists).
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How to quickly clear a JavaScript Object?
... poor GC means that IE6 will run slower, meaning that there's even more incentive to upgrade. You're still supporting it, it's just that it'll run slow.
– nickf
Mar 26 '09 at 5:47
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How to delete a remote tag?
...an 'empty' reference to the remote tag name:
git push origin :tagname
Or, more expressively, use the --delete option (or -d if your git version is older than 1.8.0):
git push --delete origin tagname
Note that git has tag namespace and branch namespace so you may use the same name for a branch and ...
When should we use mutex and when should we use semaphore
...s and the mutex are two ways to provide synchronisation. semaphore, can be more related to signalling (e.g. producer and consumer problem scenario), and mutex, can be more related to allowing access to one at a time (several requests to access shared resource, but only one granted at a time). [nice ...
MySQL Error 1093 - Can't specify target table for update in FROM clause
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Update: This answer covers the general error classification. For a more specific answer about how to best handle the OP's exact query, please see other answers to this question
In MySQL, you can't modify the same table which you use in the SELECT part.
This behaviour is documented at:
http:...