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Xcode 4 - slow performance
I have an issue with Xcode 4 really responding very slowly to user interactions, e.g. editing code, scrolling areas etc. This particularly happens with larger scale projects with many controllers/view files etc.
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A clean, lightweight alternative to Python's twisted? [closed]
A (long) while ago I wrote a web-spider that I multithreaded to enable concurrent requests to occur at the same time. That was in my Python youth, in the days before I knew about the GIL and the associated woes it creates for multithreaded code (IE, most of the time stuff just ends up serialized!...
What are the barriers to understanding pointers and what can be done to overcome them? [closed]
...s is a concept that for many can be confusing at first, in particular when it comes to copying pointer values around and still referencing the same memory block.
I've found that the best analogy is to consider the pointer as a piece of paper with a house address on it, and the memory block it refer...
JavaScript checking for null vs. undefined and difference between == and ===
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How do I check a variable if it's null or undefined...
Is the variable null:
if (a === null)
// or
if (a == null) // but see note below
...but note the latter will also be true if a is undefined.
Is it undefined:
if (typeof a === "undefined")
// o...
Programming with white text on black background?
Does anyone program with white text against black background? I have heard some rumors that it is better for your eyes. What's the case? Is it any better than the traditional black on white? What are the pros and cons?
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What is NSLayoutConstraint “UIView-Encapsulated-Layout-Height” and how should I go about forcing it
I have a UITableView running under iOS 8 and I'm using automatic cell heights from constraints in a storyboard.
17 Answer...
Why is it Valid to Concatenate Null Strings but not to Call “null.ToString()”?
...ions,the C# compiler treats a null string the same as an empty string, but it does not convert the value of the original null string.
More information on the + binary operator:
The binary + operator performs string concatenation when one or both operands are of type string.
If an operand of string...
What does “use strict” do in JavaScript, and what is the reasoning behind it?
...cently, I ran some of my JavaScript code through Crockford's JSLint , and it gave the following error:
28 Answers
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Good examples of MVVM Template
I am currently working with the Microsoft MVVM template and find the lack of detailed examples frustrating. The included ContactBook example shows very little Command handling and the only other example I've found is from an MSDN Magazine article where the concepts are similar but uses a slightly d...
deciding among subprocess, multiprocessing, and thread in Python?
I'd like to parallelize my Python program so that it can make use of multiple processors on the machine that it runs on. My parallelization is very simple, in that all the parallel "threads" of the program are independent and write their output to separate files. I don't need the threads to exchan...