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How to override to_json in Rails?
...ould be separate from the rendering of the json.
Now, anytime to_json is called on an object, as_json is invoked to create the data structure, and then that hash is encoded as a JSON string using ActiveSupport::json.encode. This happens for all types: object, numeric, date, string, etc (see the Act...
'^M' character at end of lines
...ed to the command-line. I don't know on which OS the SQL script was originally created.
16 Answers
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How to detect the device orientation using CSS media queries?
...n portrait orientation will cause the viewport to become wider than it is tall, thereby causing the browser to use landscape styles instead of portrait.
– Johann Combrink
Mar 10 '17 at 8:58
...
Iterate through every file in one directory
...lways include . and .. (the current and parent directories). You will generally not want to work on them, so you can use Dir::each_child or Dir::children (as suggested by ma11hew28) or do something like this:
Dir.foreach('/path/to/dir') do |filename|
next if filename == '.' or filename == '..'
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'IF' in 'SELECT' statement - choose output value based on column values
...tp://dev.mysql.com/doc/refman/5.0/en/control-flow-functions.html.
Additionally, you could handle when the condition is null. In the case of a null amount:
SELECT id,
IF(type = 'P', IFNULL(amount,0), IFNULL(amount,0) * -1) as amount
FROM report
The part IFNULL(amount,0) means when amount ...
python capitalize first letter only
...rn a titlecased version of S, i.e. words start with title case characters, all remaining cased characters have lower case."
– karantan
Jan 3 '17 at 11:34
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How to make a great R reproducible example
...le examples, see the help files of the function you are using. In general, all the code given there fulfills the requirements of a minimal reproducible example: data is provided, minimal code is provided, and everything is runnable. Also look at questions on Stack Overflow with lots of upvotes.
Pro...
How to go back in Eclipse?
Is there a way to go back in Eclipse? Basically, when I'm jumping around a big project following the execution flow (ctrl + click and etc.), is there a way to retrace a step? If my code calls a method and I go to the method definition, is there a key combination that will take me back to the calling...
CSS center display inline block?
...me as I need a child element with display: inline-block to be both horizontally and vertically centered within a 100% width parent.
I used Flexbox's justify-content and align-items properties, which respectively allow you to center elements horizontally and vertically. By setting both to center on...
Return array in a function
...
In this case, your array variable arr can actually also be treated as a pointer to the beginning of your array's block in memory, by an implicit conversion. This syntax that you're using:
int fillarr(int arr[])
Is kind of just syntactic sugar. You could really repla...