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Check if bash variable equals 0 [duplicate]

...and appears empty to bash. You can verify this using the below tests which all evaluate to true because xyz is either empty or unset: if [ -z ] ; then echo "true"; else echo "false"; fi xyz=""; if [ -z "$xyz" ] ; then echo "true"; else echo "false"; fi unset xyz; if [ -z "$xyz" ] ; then echo "t...
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Sign APK without putting keystore info in build.gradle

...yPassword=... keyAlias=... storeFile=... Add this to your build.gradle: allprojects { afterEvaluate { project -> def propsFile = rootProject.file('keystore.properties') def configName = 'release' if (propsFile.exists() && android.signingConfigs.hasProperty(...
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How to uncommit my last commit in Git [duplicate]

... If you aren't totally sure what you mean by "uncommit" and don't know if you want to use git reset, please see "Revert to a previous Git commit". If you're trying to understand git reset better, please see "Can you explain what "git reset" d...
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advantage of tap method in ruby

...= User.new user.username = "foobar" user.save! they would have to follow all the three lines and then recognize that it is just creating an instance named user. If it were: user = User.new.tap do |u| u.username = "foobar" u.save! end then that would be immediately clear. A reader would not...
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What does Maven do, in theory and in practice? When is it worth to use it? [closed]

...t a Java project just for practice. I've read about Maven, but I don't actually understand when it is meant to be used. 3 ...
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Creating a UIImage from a UIColor to use as a background image for UIButton [duplicate]

...'re trying to apply; the CGColor is backed by that UIColor, but ARC will deallocate the UIColor before you have a chance to use the CGColor. The clearest solution is to have a local variable pointing to your UIColor with the objc_precise_lifetime attribute. You can read more about this exact cas...
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When do I really need to use atomic instead of bool? [duplicate]

...use bool is atomic by nature? I don't think it's possible to have a partially modified bool value. When do I really need to use atomic<bool> instead of bool ? ...
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Easy way to prevent Heroku idling?

...ynos seem to keep idling - my app has very low traffic but it's also not really acceptable in my case that my users have to wait 20+ seconds to spin up a new dyno. ...
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Problem in running .net framework 4.0 website on iis 7.0

...CGI Restrictions" icon under the IIS header. Change ASP.NET 4.0 from "Not Allowed" to "Allowed". share | improve this answer | follow | ...
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Xcode duplicate/delete line

Coming from Eclipse and having been used to duplicate lines all the time, it's pretty strange finding out that Xcode has no such function. Or does it? ...