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Change a column type from Date to DateTime during ROR migration
...f you're wondering why a single change method isn't used instead of the up and down methods, it's because the change method doesn't support the change_column migration definition.
– Dennis
Feb 25 '14 at 21:35
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How do I get an empty array of any size in python?
...t the same obj appears in each element of the array. If it a mutable obj, and you modify one item, all will be changed. ...But, for this example using integers (or any other immutable type), it makes no difference. Or, if you just assign to elements, it is not a problem either. (I mention it bec...
What does the `#` operator mean in Scala?
... such a subclass. In other words, there's no A.B class, but there are a1.B and a2.B classes, and they are different classes, as the error message is telling us above.
If you did not understand that, look up path dependent types.
Now, # makes it possible for you to refer to such nested classes with...
Using IoC for Unit Testing
...y of the object graph when you do your unit tests.
– Anderson Imes
Sep 23 '09 at 14:26
4
@Mark Se...
How to destroy an object?
...ly destroy an object.
It will stay there, however if you unset the object and your script pushes PHP to the memory limits the objects not needed will be garbage collected. I would go with unset() (as opposed to setting it to null) as it seems to have better performance (not tested but documented on...
Why does C# have break if it's not optional? [duplicate]
...it fall-through behavior is often used to reduce the amount of code needed and often isn't an issue the first time that code is written. However, as code moves from the initial development phase into a maintenance phase, the code above can lead to subtle errors that are very hard to debug. These e...
AngularJS passing data to $http.get request
... {user_id: user.id}
});
See: http://docs.angularjs.org/api/ng.$http#get and https://docs.angularjs.org/api/ng/service/$http#usage (shows the params param)
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Aggregate / summarize multiple variables per group (e.g. sum, mean)
... The recast function (also from reshape2) integrates the melt and dcast function in one go for tasks like this: recast(df1, year + month ~ variable, sum, id.var = c("date", "year", "month"))
– Jaap
May 13 '16 at 6:17
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Select tableview row programmatically
...Path *)indexPath {
[self doSomethingWithRowAtIndexPath:indexPath];
}
And then, from where you wanted to call selectRowAtIndexPath, you instead call doSomethingWithRowAtIndexPath. On top of that, you can additionally also call selectRowAtIndexPath if you want the UI feedback to happen.
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Recent file history in Vim?
I would like to access recent files that I had opened and then closed in GVim. I open and close GVim frequently. I would like to access recent files from previous sessions as well.
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