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MongoDB: How to query for records where field is null or not set?
...ount({sent_at: {$exists: false}})
If its there and null, or not there at all:
db.emails.count({sent_at: null})
Refer here for querying and null
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How do I pass an object from one activity to another on Android? [duplicate]
...tom classes across activities. I have found this very useful.
Here is a small snippet of code I am using
CustomListing currentListing = new CustomListing();
Intent i = new Intent();
Bundle b = new Bundle();
b.putParcelable(Constants.CUSTOM_LISTING, currentListing);
i.putExtras(b);
i.setClass(this,...
What does the exclamation mark do before the function?
...s just a function declaration. You would need an invocation, foo(), to actually run the function.
Now, when we add the seemingly innocuous exclamation mark: !function foo() {} it turns it into an expression. It is now a function expression.
The ! alone doesn't invoke the function, of course, but w...
How to create a dialog with “yes” and “no” options?
...note: you can put a return inside the else and then you don't need to wrap all of your code in the confirm! (case by case fix though)
– Jacob Raccuia
Sep 2 '14 at 14:54
22
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How to unsubscribe to a broadcast event in angularJS. How to remove function registered via $on
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You need to store the returned function and call it to unsubscribe from the event.
var deregisterListener = $scope.$on("onViewUpdated", callMe);
deregisterListener (); // this will deregister that listener
This is found in the source code :) at least in 1.0.4. I'll j...
How do I declare a namespace in JavaScript?
... This does not create a closure for your code - it makes it tedious to call your other functions because they always have to look like: yourNamespace.bar(); I made an open source project JUST to address this design problem: github.com/mckoss/namespace.
– mckoss
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ASP.NET_SessionId + OWIN Cookies do not send to browser
...do a little more work for each request.
Back to our login problem
With all these pieces your scenarios can be explained.
Case 1 - Session was never set
System.Web.SessionState.SessionStateModule, s_sessionEverSet property is false. No session id's are generated by session state module and Syst...
Check number of arguments passed to a Bash script
...nd regex matching.
The following example checks if arguments are valid. It allows a single argument or two.
[[ ($# -eq 1 || ($# -eq 2 && $2 == <glob pattern>)) && $1 =~ <regex pattern> ]]
For pure arithmetic expressions, using (( )) to some may still be better, but they ...
Hover and Active only when not disabled
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I <3 this solution. allows me to have the following: <button class="button">hovers</button> and <button class="button no-hover>doesn't hover</button> by just using :not(.no-hover)
– Ben
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Any reason to write the “private” keyword in C#?
... the defaults, as per your question (I've never liked this argument, personally, but I figured it's worth mentioning)
It gives an impression that you've deliberately decided to make it private, rather than just gone with the defaults.
As for your last part:
Moreover is there a case where writi...