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What is Weak Head Normal Form?
...mory stats with :set +s. You can then see that foldl' f ends up allocating more thunks than foldl' f'.
– hammar
Jun 2 '17 at 15:34
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Is there a better way to find out if a local git branch exists?
...know, that's the best way to do it in a script. I'm not sure there's much more to add to that, but there might as well be one answer that just says "That command does everything you want" :)
The only thing you might want to be careful of is that branch names can have surprising characters in them,...
How do I execute a string containing Python code in Python?
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How Can I Download a File from EC2 [closed]
... copy the file into the current folder on the local machine.
You can read more here on how to access your instance with ssh if you haven't done already:
http://docs.aws.amazon.com/gettingstarted/latest/computebasics-linux/getting-started-deploy-app-connect-linux.html
When you are able to ssh as...
Handle Guzzle exception and get HTTP body
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Error type 3 Error: Activity class {} does not exist
... your device.
Simply go to Mobile Settings > Apps > [Your App] > More > Uninstall App for All Users
UPDATE for Android Studio 2.1 and up
When running Android Studio 2.1 and up you can also encounter this issue when you have the instant run option enabled in your preferences (is enable...
Using Emacs to recursively find and replace in text files not already open
...hing like this which should be easy, that especially stops me from getting more used to using Emacs and instead starting up the editor I'm already familiar with. I use the example here fairly often in editing multiple files.
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Can I add a UNIQUE constraint to a PostgreSQL table, after it's already created?
... thanks @hhaamu. Yep did try the docs but your above is much more concise.
– Thomas Browne
Jul 28 '09 at 20:17
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Drop unused factor levels in a subsetted data frame
...df,function(x) if(is.factor(x)) factor(x) else x) ...Is drop.levels() much more efficient computationally or better with large data sets? (One would have to rewrite the line above in a for-loop for a huge data frame, I suppose.)
– hatmatrix
Jul 29 '09 at 17:09
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Replace non-numeric with empty string
...ed Jan 22 '09 at 19:58
Chris Cudmore
27.5k1212 gold badges5252 silver badges9292 bronze badges
answered Nov 4 '08 at 16:54
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