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Why can't I initialize non-const static member or static array in class?
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Why I can't initialize static data members in class?
The C++ standard allows only static constant integral or enumeration types to be initialized inside the class. This is the reason a is allowed to be initialized while others are not.
Reference:
C++03 9.4.2 Static data members
§4
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How can I rename a database column in a Ruby on Rails migration?
...mething else or do nothing
end
end
For Rails 3.1 use:
While, the up and down methods still apply, Rails 3.1 receives a change method that "knows how to migrate your database and reverse it when the migration is rolled back without the need to write a separate down method".
See "Active Record...
leiningen - how to add dependencies for local jars?
I want to use leiningen to build and develop my clojure project. Is there a way to modify project.clj to tell it to pick some jars from local directories?
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How to convert currentTimeMillis to a date in Java?
...ted date do not represent correct time of the server. Is there any way to handle this elegantly ?
11 Answers
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No internet on Android emulator - why and how to fix? [closed]
I am trying to use internet with the Android emulator, but with no success.
Any ideas?
10 Answers
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java.lang.NoClassDefFoundError: Could not initialize class XXX
... properties from file
}
It would appear some uncaught exception occurred and propagated up to the actual ClassLoader attempting to load the class. We would need a stacktrace to confirm this though.
Either that or it occurred when creating PropHolder.prop static variable.
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Use of var keyword in C#
...eadable in some cases. If I have a Customer class with an Orders property, and I want to assign that to a variable, I will just do this:
var orders = cust.Orders;
I don't care if Customer.Orders is IEnumerable<Order>, ObservableCollection<Order> or BindingList<Order> - all I wan...
How do I monitor the computer's CPU, memory, and disk usage in Java?
... you use the SIGAR API. I use the SIGAR API in one of my own applications and it is great. You'll find it is stable, well supported, and full of useful examples. It is open-source with a GPL 2 Apache 2.0 license. Check it out. I have a feeling it will meet your needs.
Using Java and the Sigar ...
How to make shallow git submodules?
...dule update" can optionally clone the submodule repositories shallowly.
(And git 2.10 Q3 2016 allows to record that with git config -f .gitmodules submodule.<name>.shallow true.
See the end of this answer)
See commit 275cd184d52b5b81cb89e4ec33e540fb2ae61c1f:
Add the --depth option to th...
Insert Update stored proc on SQL Server
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Your assumption is right, this is the optimal way to do it and it's called upsert/merge.
Importance of UPSERT - from sqlservercentral.com:
For every update in the case mentioned above we are removing one
additional read from the table if we
use the UPSERT instead of EXISTS....