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What is meant by Resource Acquisition is Initialization (RAII)?
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It's a really terrible name for an incredibly powerful concept, and perhaps one of the number 1 things that C++ developers miss when they switch to other languages. There has been a bit of a movement to try to rename this concept as ...
Best way to store date/time in mongodb
...ISODate()})
> db.test.insert({date: new Date()})
> db.test.find()
{ "_id" : ObjectId("..."), "date" : ISODate("2014-02-10T10:50:42.389Z") }
{ "_id" : ObjectId("..."), "date" : ISODate("2014-02-10T10:50:57.240Z") }
The native type supports a whole range of useful methods out of the box, which...
django: BooleanField, how to set the default value to true?
...fields/#django.forms.Field.initial ) like
class MyForm(forms.Form):
my_field = forms.BooleanField(initial=True)
If you're using a ModelForm, you can set a default value on the model field ( https://docs.djangoproject.com/en/2.2/ref/models/fields/#default ), which will apply to the resulting M...
How to refer environment variable in POM.xml?
I am using maven as build tool. I have set an environment variable called env . How can I get access to this environment variable's value in the pom.xml file?
...
What is the difference between Debug and Release in Visual Studio?
... result some lines of your code might get left without any instructions at all, or some might get all mixed up. Step-by-step debugging would be impossible. Also, local variables are often optimized in mysterious ways, so Watches and QuickWatches often don't work because the variable is "optimized aw...
The order of elements in Dictionary
...when enumerating them:
foreach (KeyValuePair<string, string> kvp in _Dictionary.OrderBy(k => k.Value)) {
...
}
In framework 2.0 you would first have to put the items in a list in order to sort them:
List<KeyValuePair<string, string>> items = new List<KeyValuePair<str...
Why does one use dependency injection?
...e virtual functions and interfaces (although I do once in a blue moon) and all my configuration is magically serialized into a class using json.net (sometimes using an XML serializer).
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Perl build, unit testing, code coverage: A complete working example
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It took me a while and it also took me taking small snippets from a number of different sources and melting them together, but I think I have a small working example that sufficiently demonstrates to a Perl newbie the Perl build process including unit testing and code cove...
How to pass an array within a query string?
...s[]" value="Mercedes">
NOTE: Using field[] for multiple values is really poorly documented. I don't see any mention of it in the section on multi-valued keys in Query string - Wikipedia, or in the W3C docs dealing with multi-select inputs.
UPDATE
As commenters have pointed out, this is ve...
How to write a multidimensional array to a text file?
...is specified by the comments kwarg). (This looks more verbose than it actually is...)
import numpy as np
# Generate some test data
data = np.arange(200).reshape((4,5,10))
# Write the array to disk
with open('test.txt', 'w') as outfile:
# I'm writing a header here just for the sake of readabil...