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PostgreSQL error 'Could not connect to server: No such file or directory'
...e in my project or even try most database tasks for my Ruby on Rails 3.2 applications.
22 Answers
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How do I dump an object's fields to the console?
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Adding an inspect method to your class allows you to define how the class' attributes are displayed, rather than rely on default output. A lot of classes don't implement it well, but it can be really useful when debugging. Ruby will fall back to to_s if it can't f...
Django filter queryset __in for *every* item in list
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Summary:
One option is, as suggested by jpic and sgallen in the comments, to add .filter() for each category. Each additional filter adds more joins, which should not be a problem for small set of categories.
There is the aggregation approach. This query would be shorter and...
Trim trailing spaces in Xcode
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Starting from Xcode 4.4 whitespaces will be trimmed automatically by default, unless the line is all whitespace. You can also activate Including whitespace-only lines to fix this, which is not active by default.
Go to Xcode > Preferences > Text Editing > While editing
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Notification click: activity already open
...current task, then instead of launching a new instance of that
activity, all of the other activities on top of it will be closed and
this Intent will be delivered to the (now on top) old activity as a
new Intent.
For example, consider a task consisting of the activities: A, B, C, D.
If...
How to implement the Android ActionBar back button?
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In my situation I was looking for a way to not call onCreate of the parent when returning to it. To do this, I used your implementation, but called finish() instead of NavUtils.navigateUpFromSameTask(this). finish() calls my onStart instead of onCreate which was more ideal...
Should IBOutlets be strong or weak under ARC?
...t practice from Apple is for IBOutlets to be strong unless weak is specifically needed to avoid a retain cycle. As Johannes mentioned above, this was commented on in the "Implementing UI Designs in Interface Builder" session from WWDC 2015 where an Apple Engineer said:
And the last option I want...
Android Studio Project Structure (v.s. Eclipse Project Structure)
I'm trying to learn android development and I am initially confused by the different project structures between Eclipse and Android Studio. This makes it difficult to follow tutorials designed for Eclipse. Could anyone let me know why these differences exist? Should they exist?
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Integrating the ZXing library directly into my Android application
...de so it hopefully can help others with the same problem as I had ;)
Install Apache Ant - (See this YouTube video for config help)
Download the ZXing source from ZXing homepage and extract it
With the use of Windows Commandline (Run->CMD) navigate to the root directory of the downloaded zxing s...
Cross compile Go on OSX?
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The env command runs only that call in a custom environment and 'resets' it after it is done. For example run export GOOS=windows, then the command with or without the env and echo $GOOS afterwards. With the env the GOOS was not changed.
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