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Checking for empty queryset in Django

...is the code I refer to is only an example that it contains a line if not my_objects: to demonstrate that this is how they do it in the docs. All else is utterly irrelevant so I do not get your point. They could as well make a thousand queries and it would still be totally irrelevant as this is not t...
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Preferred way to create a Scala list

... That is, you can now work on that IndexedSeq: scala> list.foldLeft(0)(_+_) res0: Int = 55 share | improve this answer | follow | ...
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How do I use the includes method in lodash to check if an object is in the collection?

...e there is only one instance of {"b": 2}: var a = {"a": 1}, b = {"b": 2}; _.includes([a, b], b); > true On the other hand, the where(deprecated in v4) and find methods compare objects by their properties, so they don't require reference equality. As an alternative to includes, you might want t...
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How to update PATH variable permanently from Windows command line?

...mmatically add or modify system environment variables, add them to the HKEY_LOCAL_MACHINE\System\CurrentControlSet\Control\Session Manager\Environment registry key, then broadcast a WM_SETTINGCHANGE message with lParam set to the string "Environment". This allows applications, such as the shell, to ...
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Get the current first responder without using a private API

...IResponder+FirstResponder.m #import "UIResponder+FirstResponder.h" static __weak id currentFirstResponder; @implementation UIResponder (FirstResponder) +(id)currentFirstResponder { currentFirstResponder = nil; [[UIApplication sharedApplication] sendAction:@selector(findFirstRe...
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Authoritative position of duplicate HTTP GET query keys

... .NET will give you as an array (I have not cared about the order when I tested that), PHP will give you always the last and Java (at least the system I worked with based on Java) always the first value. stackoverflow.com/questions/1809494/… – SimonSimCity ...
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How do I pass the value (not the reference) of a JS variable to a function? [duplicate]

...marker, 'click', function() { change_selection(j); }); } I haven't tested it though. share | improve this answer | follow | ...
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Creating a new dictionary in Python

... Call dict with no parameters new_dict = dict() or simply write new_dict = {} share | improve this answer | follow ...
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Using mixins vs components for code reuse in Facebook React

...nding fields. Source (gist) define(function () { 'use strict'; var _ = require('underscore'); var ValidationMixin = { getInitialState: function () { return { errors: [] }; }, componentWillMount: function () { this.assertValidatorsDefined(); }, ...
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How can I get rid of an “unused variable” warning in Xcode?

...as an "unused" attribute you can use to suppress that warning: BOOL saved __attribute__((unused)) = [moc save:&error]; Alternatively (in case LLVM doesn't support the above), you could split the variable declaration into a separate line, guaranteeing that the variable would be "used" whether ...