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Referring to the null object in Python
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SyntaxError: cannot assign to keyword
It's therefore safe to assume that all None references are the same. There isn't any "custom" None.
To test for None use the is operator
When writing code you might be tempted to test for Noneness like this:
if value==None:
pass
Or to test for falsehood l...
Using DNS to redirect to another URL with a path [closed]
...mail.foo.com"
under Properties -> Static Website Hosting, set "redirect all requests to: mail.google.com/a/foo.com"
in route53, create an A record "mail.foo.com"
enable "alias", and set alias target to the "mail.foo.com" bucket
not a pure DNS solution, but it works ;)
But be aware of, the redi...
What is the preferred/idiomatic way to insert into a map?
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First of all, operator[] and insert member functions are not functionally equivalent :
The operator[] will search for the key, insert a default constructed value if not found, and return a reference to which you assign a value. Obvi...
JQuery to check for duplicate ids in a DOM
...contrast to traditional ASP.NET you're a lot more responsible for creating all the ids in your generated page. ASP.NET would give you nasty, but unique ids.
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Detect network connection type on Android
...twork is connected and fast enough to meet your demands you have to handle all the network types returned by getSubType().
It took me an hour or two to research and write this class to do just exactly that, and I thought I would share it with others that might find it useful.
Here is a Gist of the...
What are good message queue options for nodejs? [closed]
Looking to use a message queue in a small web app I'm building with node.js. I looked at resque but not sure that's appropriate. The goal is to push notifications to clients based on backend and other client actions with socketio. I could do this with just socketio but I thought maybe a proper messa...
C# 5 async CTP: why is internal “state” set to 0 in generated code before EndAwait call?
... code looked like, and the GetAwaiter() / BeginAwait() / EndAwait() calls.
4 Answers
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Mongoose, Select a specific field with find
... I think .select just is a filter to choose field after you get all of that, my recommendation is to use .find({}, 'name -_id')
– hong4rc
Mar 2 '19 at 16:15
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How do I parse an ISO 8601-formatted date?
... Pypi name is python-dateutil, not dateutil (thanks code3monk3y):
pip install python-dateutil
If you're using Python 3.7, have a look at this answer about datetime.datetime.fromisoformat.
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how to use javascript Object.defineProperty
...rs = new Product("Sneakers",20);
sneakers.discount = 50; // 50, setter is called
sneakers.discount+= 20; // 70, setter is called
sneakers.discount+= 20; // 80, not 90!
alert(sneakers.discount); // getter is called
Note the last but one line: the responsibility for correct discount value was moved ...