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What's the point of map in Haskell, when there is fmap?
...feel the need for a map function? Couldn't it just be what is currently known as fmap and fmap could be removed from the language?
...
getting the screen density programmatically in android?
...g point scaling factor from the reference density (160dpi). The same value now provided by metrics.densityDpi can be calculated
int densityDpi = (int)(metrics.density * 160f);
share
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improve this...
How to redirect to a 404 in Rails?
...self, there's no reason to; Rails has this functionality built in already. If you want to show a 404 page, create a render_404 method (or not_found as I called it) in ApplicationController like this:
def not_found
raise ActionController::RoutingError.new('Not Found')
end
Rails also handles Abs...
Failed to Attach to Process ID Xcode
...xperienced this problem?
Yesterday I still can run my app in simulator but now I cannot run my app since Xcode prints this error in console:
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Objective-C: difference between id and void *
...
void * means "a reference to some random chunk o' memory with untyped/unknown contents"
id means "a reference to some random Objective-C object of unknown class"
There are additional semantic differences:
Under GC Only or GC Supported modes, the compiler will emit write barriers for references...
Best way to select random rows PostgreSQL
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Given your specifications (plus additional info in the comments),
You have a numeric ID column (integer numbers) with only few (or moderately few) gaps.
Obviously no or few write operations.
Your ID column has to be indexed! A primary key...
Remove empty elements from an array in Javascript
... when there were not many useful built-in methods in the Array.prototype.
Now, certainly, I would recommend you to use the filter method.
Take in mind that this method will return you a new array with the elements that pass the criteria of the callback function you provide to it.
For example, if ...
Android Gallery on Android 4.4 (KitKat) returns different URI for Intent.ACTION_GET_CONTENT
...
Try this:
if (Build.VERSION.SDK_INT <19){
Intent intent = new Intent();
intent.setType("image/jpeg");
intent.setAction(Intent.ACTION_GET_CONTENT);
startActivityForResult(Intent.createChooser(intent, getResources().g...
ObservableCollection not noticing when Item in it changes (even with INotifyPropertyChanged)
...Changed;
}
public void ContentCollectionChanged(object sender, NotifyCollectionChangedEventArgs e)
{
//This will get called when the collection is changed
}
}
Okay, that's twice today I've been bitten by the MSDN documentation being wrong. In the link I gave you it says:...
Selecting a row of pandas series/dataframe by integer index
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What if you wanted the 2nd AND 3rd AND 4th row?
– FaCoffee
Nov 7 '16 at 20:36
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