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What are enums and why are they useful?
Today I was browsing through some questions on this site and I found a mention of an enum being used in singleton pattern about purported thread safety benefits to such solution.
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Always pass weak reference of self into block in ARC?
...am a little confused about block usage in Objective-C. I currently use ARC and I have quite a lot of blocks in my app, currently always referring to self instead of its weak reference. May that be the cause of these blocks retaining self and keeping it from being dealloced ? The question is, sho...
What's the difference between a proc and a lambda in Ruby?
And when would you use one rather than the other?
8 Answers
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What's the difference between detaching a Fragment and removing it?
In the Android docs for a FragmentTransaction I noticed two very similar methods: detach and remove . The descriptions over there don't seem to provide much insight about when to use each, and from what I can tell they appear to be the same.
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When to use single quotes, double quotes, and backticks in MySQL
I am trying to learn the best way to write queries. I also understand the importance of being consistent. Until now, I have randomly used single quotes, double quotes, and backticks without any real thought.
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Why can't C++ be parsed with a LR(1) parser?
I was reading about parsers and parser generators and found this statement in wikipedia's LR parsing -page:
6 Answers
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When and why I should use session_regenerate_id()?
Why and when should I use the session_regenerate_id() function in php?
Should I always use it after I use the session_start() ?
I've read that I have to use it to prevent session fixation, is this the only reason?
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Difference between Fact table and Dimension table?
...en reading a book for business objects, I came across the term- fact table and dimension table.
9 Answers
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Why is “throws Exception” necessary when calling a function?
Why compiler reports that methods show2() , show3() , and main() have
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How and where are Annotations used in Java?
...n be used to describe other meta-objects. Meta-objects are classes, fields and methods. Asking an object for its meta-object (e.g. anObj.getClass() ) is called introspection. The introspection can go further and we can ask a meta-object what are its annotations (e.g. aClass.getAnnotations). Introspe...