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How to “test” NoneType in python?
...r is not None.
Original Answer:
The simplest way however, without the extra line in addition to cardamom's answer is probably:
isinstance(x, type(None))
So how can I question a variable that is a NoneType? I need to use if method
Using isinstance() does not require an is within the if-s...
What is “pom” packaging in maven?
...r packaging types.
We use pom packaging for many of our projects and bind extra phases and goals as appropriate.
For example some of our applications use:
prepare-package -> test -> package -> install -> deploy
When you mvn install the application it should add it to your locally .m...
Performance surprise with “as” and nullable types
... JIT
TestUnrestricted<int>(1,5);
TestUnrestricted<string>("abc",5);
TestUnrestricted<int?>(1,5);
TestNullable<int>(1, 5);
const int LOOP = 100000000;
Console.WriteLine(TestUnrestricted<int>(1, LOOP));
Console.Writ...
The import javax.servlet can't be resolved [duplicate]
...vlet API the server provides.
Following steps solved it without adding an extra Servlet-API to the Java Build Path (Eclipse version: Luna):
Right click on your "Dynamic Web Project"
Select Properties
Select Project Facets in the list on the left side of the "Properties" wizard
On the right side o...
Solving a “communications link failure” with JDBC and MySQL [duplicate]
... connecting to the server. Maybe the problem is because of the wrong query string or too many connections to the database.
So I suggest you to try all the solutions one by one and don't give up!
Here are the solutions that I found on the internet and for each of them, there is at least on person w...
Struct like objects in Java
...s and setters. A possible solution would look like this:
public property String foo;
a->Foo = b->Foo;
Update: It's highly unlikely that property support will be added in Java 7 or perhaps ever. Other JVM languages like Groovy, Scala, etc do support this feature now. - Alex Miller
...
AWS MySQL RDS vs AWS DynamoDB [closed]
... DynamoDB is really a bad idea. Best laid plans etc., you always need that extra flexibility from your DB.
Here are our reasons we moved from DynamoDB:
Indexing - Changing or adding keys on-the-fly is impossible without creating a new table.
Queries - Querying data is extremely limited. Especia...
How do you rename a MongoDB database?
...atabase name, so to rename a set of database files, every single namespace string would have to be rewritten. This impacts:
the .ns file
every single numbered file for the collection
the namespace for every index
internal unique names of each collection and index
contents of system.n...
PHP json_decode() returns NULL with valid JSON?
...ked for me
json_decode( preg_replace('/[\x00-\x1F\x80-\xFF]/', '', $json_string), true );
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What's the use/meaning of the @ character in variable names in C#?
...ing, in VB.NET you can use [ ] to specify a verbatim identifier, e.g. Dim [String] As String.
– MicroVirus
Apr 28 '14 at 11:24
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