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Can inner classes access private variables?
This errors out when I compile with class Outer::Inner' has no member named `var'
5 Answers
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What is a PDB file?
... as it allows exceptions to be traced to a specific line in your code. Without the symbols in the pdb file, you will find it hard to pinpoint specific problems in order to solve them. You don't necessarily need to exclude them from release builds either, as sometimes the extra information in a big r...
How to fix the uninitialized constant Rake::DSL problem on Heroku?
...
I solved this, finally, after a lot of mucking about. The short version of what I did, missing out the many experiments, was this:
1) change the Gemfile to specify Rake 0.8.7
#in Gemfile
gem "rake", "0.8.7"
2) Take out a hack that I had previously added to Rakefile bas...
Understanding __get__ and __set__ and Python descriptors
...mple), it could store the value on itself and not its class.
An article about descriptors can be found here.
EDIT: As jchl pointed out in the comments, if you simply try Temperature.celsius, instance will be None.
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Physical vs. logical / soft delete of database record?
...hat you keep the history (good for auditing) and you don't have to worry about cascading a delete through various other tables in the database that reference the row you are deleting. Disadvantage is that you have to code any reporting/display methods to take the flag into account.
As far as if it...
Are arrays passed by value or passed by reference in Java? [duplicate]
...t[2];
arr[0] = 4;
arr[1] = 5;
changeContent(arr);
System.out.println(arr[0]); // Will print 10..
changeRef(arr);
System.out.println(arr[0]); // Will still print 10..
// Change the reference doesn't reflect change here..
}
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Mock functions in Go
... (or any mocking framework for that matter; mocking in Go is very easy without it). I would either pass a dependency to the downloader() function as a parameter, or I would make downloader() a method on a type, and the type can hold the get_page dependency:
Method 1: Pass get_page() as a parameter o...
Principal component analysis in Python
...cipal components that account for e.g.
90 % of the total variance
Out:
p.U, p.d, p.Vt: from numpy.linalg.svd, A = U . d . Vt
p.dinv: 1/d or 0, see NR
p.eigen: the eigenvalues of A*A, in decreasing order (p.d**2).
eigen[j] / eigen.sum() is variable j's fraction of the tot...
Shall we always use [unowned self] inside closure in Swift
...troller where that request is used to populate the view. If the user backs out, we no longer need to populate the view, nor do we need a reference to the view controller.
– David James
Mar 30 '16 at 14:41
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Best way to compare two complex objects
...strings... testing string equality is one of the most optimized operations out there.... you may have a point with reflection... but on the whole serialization will not be "orders of magnitude" worse than other methods. You should do benchmarks if you suspect performance problems... I have not expe...