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Double not (!!) operator in PHP
...egardless of the operand. Then the left ! will negate that boolean.
This means that for any true value (numbers other than zero, non-empty strings and arrays, etc.) you will get the boolean value TRUE, and for any false value (0, 0.0, NULL, empty strings or empty arrays) you will get the boolean v...
How to delete a record in Django models?
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There are a couple of ways:
To delete it directly:
SomeModel.objects.filter(id=id).delete()
To delete it from an instance:
instance = SomeModel.objects.get(id=id)
instance.delete()
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How can I remove a flag in C?
There is a variable that holds some flags and I want to remove one of them. But I don't know how to remove it.
3 Answers
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Making a Location object in Android with latitude and longitude values
I have a program in which latitude and longitude values of a location are stored in a database, which I download.
3 Answer...
Creating a new column based on if-elif-else condition
I have a DataFrame df :
4 Answers
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What is two way binding?
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Two-way binding just means that:
When properties in the model get updated, so does the UI.
When UI elements get updated, the changes get propagated back to the model.
Backbone doesn't have a "baked-in" implementation of #2 (although you can cer...
What's a standard way to do a no-op in python?
I often find myself writing if / elif / else constructs in python, and I want to include options which can occur, but for which the corresponding action is to do nothing. I realise I could just exclude those if statements, but for readability I find it helps to include them all, so that if you are l...
:after vs. ::after
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It's pseudo-class vs pseudo-element distinction.
Except for ::first-line, ::first-letter, ::before and ::after (which have been around a little while and can be used with single colons if you require IE8 support), pseudo-elements require double colons.
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Rails migrations: self.up and self.down versus change
Looks like the new rails version has "change" versus self.up and self.down methods.
3 Answers
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Nginx not picking up site in sites-enabled?
...over 10 hours of research I have not figured out why this doesn't work! I am trying to move my localhost to my sites-enabled folder which is in /etc/nginx/sites-enabled/default.
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