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How does Haskell printf work?
...ase, we have no extra arguments, so we need to be able to instantiate r to IO (). For this, we have the instance
instance PrintfType (IO ())
Next, in order to support a variable number of arguments, we need to use recursion at the instance level. In particular we need an instance so that if r is ...
How can you represent inheritance in a database?
...this model also comes with a few disadvantages:
The common attributes are mixed with the subtype specific attributes, and there is no easy way to identify them. The database will not know either.
When defining the tables, you would have to repeat the common attributes for each subtype table. That'...
How do I write JSON data to a file?
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You forgot the actual JSON part - data is a dictionary and not yet JSON-encoded. Write it like this for maximum compatibility (Python 2 and 3):
import json
with open('data.json', 'w') as f:
json.dump(data, f)
On a modern system (i.e. Python 3 and UTF-8 support), you...
How can we match a^n b^n with Java regex?
...hy at the same time making both possessive would also work (though perhaps mixing mandatory and non-mandatory possessive quantifier in the same pattern may lead to misperceptions).
It should also be said that while it's neat that there's a regex pattern that will match anbn, this is in not always th...
Not able to type in textfield in iphone simulator using Mac Keyboard?
I'm working on a basic iOS app which supports both portrait and landscape modes. When the iPhone simulator keyboard is open in landscape and I'm switching the app to portrait mode I'm unable to type anything in any text field using my Mac physical keyboard.
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iOS: Multi-line UILabel in Auto Layout
I'm having trouble trying to achieve some very basic layout behavior with Auto Layout. My view controller looks like this in IB:
...
Set a default font for whole iOS app?
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It seems to be possible in iOS 5 using the UIAppearance proxy.
[[UILabel appearance] setFont:[UIFont fontWithName:@"YourFontName" size:17.0]];
That will set the font to be whatever your custom font is for all UILabels in your app. You'll need to re...
How to bundle a native library and a JNI library inside a JAR?
The library in question is Tokyo Cabinet .
7 Answers
7
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How do I create a file and write to it in Java?
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Note that each of the code samples below may throw IOException. Try/catch/finally blocks have been omitted for brevity. See this tutorial for information about exception handling.
Note that each of the code samples below will overwrite the file if it already exists
Creating...
Get size of folder or file
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java.io.File file = new java.io.File("myfile.txt");
file.length();
This returns the length of the file in bytes or 0 if the file does not exist. There is no built-in way to get the size of a folder, you are going to have to walk...