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Unique BooleanField value in Django?
Suppose my models.py is like so:
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What is the purpose of the word 'self'?
What is the purpose of the self word in Python? I understand it refers to the specific object created from that class, but I can't see why it explicitly needs to be added to every function as a parameter. To illustrate, in Ruby I can do this:
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What's the difference between UTF-8 and UTF-8 without BOM?
What's different between UTF-8 and UTF-8 without a BOM ? Which is better?
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One DbContext per web request… why?
...s explaining how to set up Entity Framework's DbContext so that only one is created and used per HTTP web request using various DI frameworks.
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Understanding events and event handlers in C#
...ents, especially within the context of creating user interfaces. I think this is the prototype for creating an event:
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Ruby on Rails Server options [closed]
The whole issue of setting up a development server for my Ruby on Rails application confuses me. There are WEBrick, Mongrel, Passenger, Apache, Nginx and many more I am sure, and I don't really understand the different roles they play.
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What's the difference between a word and byte?
I've done some research.
A byte is 8 bits and a word is the smallest unit that can be addressed on memory. The exact length of a word varies. What I don't understand is what's the point of having a byte? Why not say 8 bits?
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String, StringBuffer, and StringBuilder
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Mutability Difference:
String is immutable, if you try to alter their values, another object gets created, whereas StringBuffer and StringBuilder are mutable so they can change their values.
Thread-Safety Difference:
The difference between StringBuffer ...
Fast permutation -> number -> permutation mapping algorithms
... first element ends up at, you have n possibilities, so you can describe this with a number between 0 and n-1. For the position that the next element ends up at, you have n-1 remaining possibilities, so you can describe this with a number between 0 and n-2.
Et cetera until you have n numbers.
As a...
Why are const parameters not allowed in C#?
...t actually did that, that would be great. Const doesn't do that. The const is a lie!
Const doesn't provide any guarantee that I can actually use. Suppose you have a method that takes a const thing. There are two code authors: the person writing the caller and the person writing the callee. The auth...