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scopes with lambda and arguments in Rails 4 style?
...Ruby 1.9, the short lambda syntax does not allow a space between the arrow and a parameter (scope :find_lazy, ->(param)). In Ruby 2+, the space is allowed. More info here...
– furman87
Aug 22 '15 at 19:07
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iPhone - Grand Central Dispatch main thread
I have been using with success, grand central dispatch in my apps, but I was wondering what is the real advantage of using something like this:
...
Non-static method requires a target
I have a controller action that works fine on Firefox both locally and in production, and IE locally, but not IE in production. Here is my controller action:
...
How does a hash table work?
... in layman's terms.
Let's assume you want to fill up a library with books and not just stuff them in there, but you want to be able to easily find them again when you need them.
So, you decide that if the person that wants to read a book knows the title of the book and the exact title to boot, the...
how to check if List element contains an item with a Particular Property Value
...
If you have a list and you want to know where within the list an element exists that matches a given criteria, you can use the FindIndex instance method. Such as
int index = list.FindIndex(f => f.Bar == 17);
Where f => f.Bar == 17 is ...
Android - Camera preview is sideways
...a.setParameters(parameters);
previewCamera();
}
And the previewCamera method :
public void previewCamera() {
try {
mCamera.setPreviewDisplay(mSurfaceHolder);
mCamera.startPreview();
isPreviewRunning = true;
} ca...
How to remove last n characters from every element in the R vector
I am very new to R, and I could not find a simple example online of how to remove the last n characters from every element of a vector (array?)
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Why do you have to call .items() when iterating over a dictionary in Python?
...f least astonishment, in would also have to take such a tuple as its left-hand operand in the containment check.
How useful would that be? Pretty useless indeed, basically making if (key, value) in C a synonym for if C.get(key) == value -- which is a check I believe I may have performed, or wanted...
What is the meaning of “non temporal” memory accesses in x86
...to be seen by other processors in a timely fashion.
When data is produced and not (immediately) consumed again, the fact that memory store operations read a full cache line first and then modify the cached data is detrimental to performance. This operation pushes data out of the caches which might ...
Does MySQL ignore null values on unique constraints?
...sult:
x
NULL
NULL
1
This is not true for all databases. SQL Server 2005 and older, for example, only allows a single NULL value in a column that has a unique constraint.
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