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Sending a message to nil in Objective-C
As a Java developer who is reading Apple's Objective-C 2.0 documentation: I wonder what " sending a message to nil " means - let alone how it is actually useful. Taking an excerpt from the documentation:
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Explain “claims-based authentication” to a 5-year-old
Well, not exactly to a 5-year-old, but please avoid buzzword and enterprisespeak if possible.
6 Answers
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Reverting a single file to a previous version in git [duplicate]
Is there a way to go through different commits on a file.
Say I modified a file 5 times and I want to go back to change 2, after I already committed and pushed to a repository.
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Is Javascript a Functional Programming Language?
Just because functions are first class objects, there are closures, and higher order functions, does Javascript deserve to be called a Functional Programming language? The main thing I think it lacks is Pure Functions, and it doesn't 'feel' like other functional languages, like lisp (although thats...
Why does NULL = NULL evaluate to false in SQL server
In SQL server if you have nullParam=NULL in a where clause, it always evaluates to false. This is counterintuitive and has caused me many errors. I do understand the IS NULL and IS NOT NULL keywords are the correct way to do it. But why does SQL server behave this way?
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Use of “global” keyword in Python
What I understand from reading the documentation is that Python has a separate namespace for functions, and if I want to use a global variable in that function, I need to use global .
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Randomize a List
What is the best way to randomize the order of a generic list in C#? I've got a finite set of 75 numbers in a list I would like to assign a random order to, in order to draw them for a lottery type application.
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Passing a dictionary to a function as keyword parameters
I'd like to call a function in python using a dictionary.
4 Answers
4
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What does character set and collation mean exactly?
I can read the MySQL documentation and it's pretty clear. But, how does one decide which character set to use? On what data does collation have an effect?
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When should I use mmap for file access?
POSIX environments provide at least two ways of accessing files. There's the standard system calls open() , read() , write() , and friends, but there's also the option of using mmap() to map the file into virtual memory.
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