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Python super() raises TypeError
...You have to design any methods that need to multiply-inherit (most notably __init__) to pass through arguments in a clean and sensible way, otherwise you'll get TypeErrors or worse debugging problems when someone tries to multiply-inherit using your class. Unless you've really designed to support MI...
Apache Spark: map vs mapPartitions?
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I'm seeing the opposite -- even with very small operations, its faster to call mapPartitions and iterate than call map. I am assuming that this is just the overhead of starting the language engine that will process the map task. (I'm in R, which may have more startup...
How to read environment variables in Scala
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I would also prefer Properties. It allows to retrieve Optionals, and has names for commonly used properties.
– ppopoff
Dec 17 '15 at 14:46
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ASP.NET MVC: Is Controller created for every request?
...ther controller.
The short version is that ControllerActivator.Create is called (for every request) to create a Controller (which inits a new Controller either through the DependencyResolver or through the Activator if no Resolver has been set up):
public IController Create(RequestContext requestC...
What does && mean in void *p = &&abc;
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@Lundin: Same can be said of most compilers. __forceinline? __declspec(naked)? One of my favourite MSVCisms is: template<typename T> class X { friend T; }, which is invalid C++03.
– Sebastian Mach
Aug 17 '12 at 8:20
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What does the “@” symbol mean in reference to lists in Haskell?
...hout the @, you'd have to choose between (1) or (2):(3).
This syntax actually works for any constructor; if you have data Tree a = Tree a [Tree a], then t@(Tree _ kids) gives you access to both the tree and its children.
s...
How do you write a migration to rename an ActiveRecord model and its table in Rails?
...ble_name
end
end
I had to go and rename the model declaration file manually.
Edit:
In Rails 3.1 & 4, ActiveRecord::Migration::CommandRecorder knows how to reverse rename_table migrations, so you can do this:
class RenameOldTableToNewTable < ActiveRecord::Migration
def change
rena...
Right way to initialize an OrderedDict using its constructor such that it retains order of initial d
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See __hash__. Specifically about the str type.
– metatoaster
Aug 25 '14 at 6:43
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What's the idiomatic syntax for prepending to a short python list?
... @MattM. If you insert at the front of a list, python has to move all the other items one space forwards, lists can't "make space at the front". collections.deque (double ended queue) has support for "making space at the front" and is much faster in this case.
– fejfo
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Why can't I assign a *Struct to an *Interface?
... var pi *Interface
pi = new(Interface)
*pi = ps
_, _ = pi, ps
}
Compiles OK. See also here.
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