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unable to install pg gem
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I had this problem, this worked for me:
Install the postgresql-devel package, this will solve the issue of pg_config missing.
sudo apt-get install libpq-dev
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How to create a hex dump of file containing only the hex characters without spaces in bash?
...te an unmodified hex dump of a binary file in Linux using bash? The od and hexdump commands both insert spaces in the dump and this is not ideal.
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Why is @autoreleasepool still needed with ARC?
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ARC doesn't get rid of retains, releases and autoreleases, it just adds in the required ones for you. So there are still calls to retain, there are still calls to release, there are still calls to autorelease and there are still auto release pools.
One of the other...
How to get .app file of a xcode application
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Build a release version, and the .app file is under build/Release folder of your project. Just copy it to Applications folder of your friend's machine. I don't think you need to build a installer.
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iOS (iPhone, iPad, iPodTouch) view real-time console log terminal
Is there a way to view the real-time console log to view NSLog and other debug messages in a real-time manner, such as adb logcat?
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MySQL > Table doesn't exist. But it does (or it should)
I changed the datadir of a MySQL installation and all the bases moved correctly except for one.
I can connect and USE the database. SHOW TABLES also returns me all the tables correctly, and the files of each table exists on the MySQL data directory.
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How should I escape strings in JSON?
...ary in your language that you can feed some appropriate data structure to, and let it worry about how to escape things. It'll keep you much saner. If for whatever reason you don't have a library in your language, you don't want to use one (I wouldn't suggest this¹), or you're writing a JSON library...
Getting the error “Missing $ inserted” in LaTeX
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The "Missing $ inserted" is probably caused by the underscores and bars. These characters in LaTeX have special meaning in math mode (which is delimited by $ characters). Try escaping them; e.g. update\_element instead of update_element.
However, if you're trying to display code, a bet...
Case objects vs Enumerations in Scala
...es. However, I find in general that enumerations are a bit clumsy in Scala and have the feel of an awkward add-on, so I now tend to use case objects. A case object is more flexible than an enum:
sealed trait Currency { def name: String }
case object EUR extends Currency { val name = "EUR" } //etc.
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Quit and restart a clean R session from within R?
Is there a way I can make an alias, within R, that will execute q() and then restart a clean R session?
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