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Swift: Testing optionals for nil
...let
guard let can do similar things. It's main purpose is to make it logically more reasonable. It's like saying Make sure the variable is not nil, otherwise stop the function. guard let can also do extra condition checking as if let.
The differences are that the unwrapped value will be available ...
How to compare files from two different branches?
...verged from mybranch (but without new changes since then in mybranch).
In all cases, the -- separator before the file name indicates the end of command line flags. This is optional unless Git will get confused if the argument refers to a commit or a file, but including it is not a bad habit to get ...
Change text color based on brightness of the covered background area?
...swered Aug 8 '12 at 15:38
Alex BallAlex Ball
3,73622 gold badges1313 silver badges2121 bronze badges
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How to avoid soft keyboard pushing up my layout? [duplicate]
...eyboard always pushes up my navigation buttons, even though it doesn't actually block the textview. It makes my UI looks funny. How can I force my navigation buttons to stay static where they are without ever being pushed by the soft keyboard? I have tried to set the Activity's windowSoftInputMode, ...
How to get distinct values from an array of objects in JavaScript?
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@zhuguowei perhaps, although there's nothing really wrong with sparse arrays - and I also assumed that age is a relatively small integer (<120 surely)
– Niet the Dark Absol
Jun 12 '17 at 14:56
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Django optional url parameters
...r, easier to follow way is to have multiple rules that matches your needs, all pointing to the same view.
urlpatterns = patterns('',
url(r'^project_config/$', views.foo),
url(r'^project_config/(?P<product>\w+)/$', views.foo),
url(r'^project_config/(?P<product>\w+)/(?P<pro...
C++ obtaining milliseconds time on Linux — clock() doesn't seem to work properly
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Please note that clock does not measure wall clock time. That means if your program takes 5 seconds, clock will not measure 5 seconds necessarily, but could more (your program could run multiple threads and so could consume more CPU than real time) or less. It measu...
Converting array to list in Java
... new ArrayList<Integer>(Arrays.asList(values));
First approach actually does not convert array but 'represents' it like a List. But array is under the hood with all its properties like fixed number of elements. Please note you need to specify type when constructing ArrayList.
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Visually managing MongoDB documents and collections [closed]
... have to keep searching for documents, copy-and-pasting OIDs, etc., especially from a command prompt window (ever tried to "mark" text that wraps multiple lines?)
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Creating an array of objects in Java
...is:
A a1;
A a2;
A a3;
A a4;
Now you couldn't do a1.someMethod() without allocating a1 like this:
a1 = new A();
Similarly, with the array you need to do this:
a[0] = new A();
...before using it.
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