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Check if value already exists within list of dictionaries?
...d also be missing the above code can give you a KeyError. You can fix this by using get and providing a default value. If you don't provide a default value, None is returned.
if not any(d.get('main_color', default_value) == 'red' for d in a):
# does not exist
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Git: updating remote branch information
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That will remove all branches that are no longer tracked by the remote repository. So, just be careful.
– Garrett Hyde
Oct 22 '10 at 2:51
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What's the correct way to communicate between controllers in AngularJS?
...rootScope.$on. The former can cause serious performance problems as raised by @numan. That is because the event will bubble down through all scopes.
However, the latter (using $rootScope.$emit + $rootScope.$on) does not suffer from this and can therefore be used as a fast communication channel!
F...
How to check if an app is installed from a web-page on an iPhone?
... either to your app, if it is installed, or to the App Store.
You do this by adding a meta tag to the page. You can even specify a detailed app URL if you want the app to do something special when it loads.
Details are at Apple's Promoting Apps with Smart App Banners page.
The mechanism has the ...
XMLHttpRequest cannot load file. Cross origin requests are only supported for HTTP
...script, and frameworks like jQuery and angularJs; and test everything just by using the Notepad++ menu item, RUN, LAUNCH IN FIREFOX. That's a nice, easy way to start creating a web page, but when you start creating anything more than layout, css and simple page navigation, you need a local server s...
What is the motivation for bringing Symbols to ES6?
...n some other crazy stuff). I always thought that the :symbol notion in Ruby is needless; we could easily use plain strings instead, like we do in JavaScript. And now they decide to complicate things in JS with that.
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jQuery .val change doesn't change input value
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This is totally correct, by using setAttribute or jQuery's attr you will also affect the DOM element's value: jsfiddle.net/a8SxF/1
– TheZ
Aug 8 '12 at 21:58
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How to set -source 1.7 in Android Studio and Gradle
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FIle-> Other Settings -> Default Settings -> Compiler (Expand it by clicking left arrow) -> Java Compiler -> You can change the Project bytecode version here
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Display current time in 12 hour format with AM/PM
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Easiest way to get it by using date pattern - h:mm a, where
h - Hour in am/pm (1-12)
m - Minute in hour
a - Am/pm marker
Code snippet :
DateFormat dateFormat = new SimpleDateFormat("hh:mm a");
Read more on documentation - SimpleDateFormat ...
Or versus OrElse
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OrElse is a short-circuiting operator, Or is not.
By the definition of the boolean 'or' operator, if the first term is True then the whole is definitely true - so we don't need to evaluate the second term.
OrElse knows this, so doesn't try and evaluate temp = 0 once it's es...