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const char * const versus const char *?
...e myself with C++ and I have run into the following question. First, here is the example code:
12 Answers
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What is the difference between g++ and gcc?
What is the difference between g++ and gcc? Which one of them should be used for general c++ development?
10 Answers
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Creating a segue programmatically
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By definition a segue can't really exist independently of a storyboard. It's even there in the name of the class: UIStoryboardSegue. You don't create segues programmatically - it is the storyboard runtime that creates them for you. You can normally call perfo...
How to check if string input is a number? [duplicate]
How do I check if a user's string input is a number (e.g. -1 , 0 , 1 , etc.)?
24 Answers
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What is a regular expression which will match a valid domain name without a subdomain?
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/^[a-zA-Z0-9][a-zA-Z0-9-]{1,61}[a-zA-Z0-9]\.[a-zA-Z]{2,}$/
But note this will reject a lot of valid domains.
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Check for installed packages before running install.packages() [duplicate]
I have an R script that is shared with several users on different computers. One of its lines contains the install.packages("xtable") command.
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Is there any Rails function to check if a partial exists?
When I render a partial which does not exists, I get an Exception. I'd like to check if a partial exists before rendering it and in case it doesn't exist, I'll render something else. I did the following code in my .erb file, but I think there should be a better way to do this:
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Why is 128==128 false but 127==127 is true when comparing Integer wrappers in Java?
...eger (capital I) the compiler emits:
Integer b2 =Integer.valueOf(127)
This line of code is also generated when you use autoboxing.
valueOf is implemented such that certain numbers are "pooled", and it returns the same instance for values smaller than 128.
From the java 1.6 source code, line 621...
What's the difference between ConcurrentHashMap and Collections.synchronizedMap(Map)?
I have a Map which is to be modified by several threads concurrently.
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Why is semicolon allowed in this python snippet?
Python does not warrant the use of semicolons to end statements.
So why is this (below) allowed?
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