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Why dict.get(key) instead of dict[key]?
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It allows you to provide a default value if the key is missing:
dictionary.get("bogus", default_value)
returns default_value (whatever you choose it to be), whereas
dictionary["bogus"]
would raise a KeyError.
If omitted...
what is reverse() in Django
...!-- django <= 1.4 -->
<a href="{% url url_name %}">link which calls some_view</a>
<!-- django >= 1.5 or with {% load url from future %} in your template -->
<a href="{% url 'url_name' %}">link which calls some_view</a>
This will be rendered as:
<a href="...
How to access the correct `this` inside a callback?
...d inside each function and its value only depends on how the function was called, not how/when/where it was defined. It is not affected by lexical scopes like other variables (except for arrow functions, see below). Here are some examples:
function foo() {
console.log(this);
}
// normal functio...
How to change the type of a field?
...(x)) and then save the document again.
If you need to do this programmatically and entirely from the shell, you can use the find(...).forEach(function(x) {}) syntax.
In response to the second comment below. Change the field bad from a number to a string in collection foo.
db.foo.find( { 'bad' :...
Why split the tag when writing it with document.write()?
...lt;script> and/or </script> tags up within document.write() calls?
5 Answers
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Java: Calling a super method which calls an overridden method
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The keyword super doesn't "stick". Every method call is handled individually, so even if you got to SuperClass.method1() by calling super, that doesn't influence any other method call that you might make in the future.
That means there is no direct way to call SuperClass.m...
Can PostgreSQL index array columns?
... to this question in the documentation. If a column is an array type, will all the entered values be individually indexed?
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When using a Settings.settings file in .NET, where is the config actually stored?
When using a Settings.settings file in .NET, where is the config actually stored?
I want to delete the saved settings to go back to the default state, but can't find where it's stored... any ideas?
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Elegant setup of Python logging in Django
...nowhere else. You can either use a configuration file or do it programmatically step-by-step - it just depends on your requirements. The key thing is that I usually add the handlers I want to the root logger, using levels and sometimes logging.Filters to get the events I want to the appropriate file...
How do I add the contents of an iterable to a set?
What is the "one [...] obvious way" to add all items of an iterable to an existing set ?
6 Answers
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