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How can i query for null values in entity framework?
...g this bug!
For backwards compatibility, it will be opt-in - you need manually enable a setting to make entry == value work. No word yet on what this setting is. Stay tuned!
Edit 2: According to this post by the EF team, this issue has been fixed in EF6! Woohoo!
We changed the default be...
How to organize a node app that uses sequelize?
...ike fields, relationships and options.
Have a singleton module which loads all those files and setup all the model classes and relationships.
Setup your singleton module at the app.js file.
Get the model classes from the singleton module do not use require on your model files, load the models from t...
Is there a typical state machine implementation pattern?
...
Really nice touch how NUM_STATES is defined.
– Albin Stigo
Dec 19 '15 at 19:38
| ...
Is there an expression for an infinite generator?
...
for x in iter(int, 1): pass
Two-argument iter = zero-argument callable + sentinel value
int() always returns 0
Therefore, iter(int, 1) is an infinite iterator. There are obviously a huge number of variations on this particular theme (especially once you add lambda into the mix). One va...
How to concatenate properties from multiple JavaScript objects
...n Javascript.
The Object.assign() method is used to copy the values of all enumerable own properties from one or more source objects to a target object. It will return the target object.
MDN documentation on Object.assign()
var o1 = { a: 1 };
var o2 = { b: 2 };
var o3 = { c: 3 };
var...
Python function attributes - uses and abuses [closed]
...
I typically use function attributes as storage for annotations. Suppose I want to write, in the style of C# (indicating that a certain method should be part of the web service interface)
class Foo(WebService):
@webmethod
de...
Any way to make a WPF textblock selectable?
How to allow TextBlock 's text to be selectable?
15 Answers
15
...
Event system in Python
...r methods', which is a
simple implementation of the Observer pattern.
Basically, the handler methods (callables) are stored in an array and are each called when the event 'fires'.
Publish-Subscribe
The disadvantage of Observer event systems is that you can only register the handlers on the actual Ev...
MD5 algorithm in Objective-C
...ENGTH];
CC_MD5( cStr, (int)strlen(cStr), result ); // This is the md5 call
return [NSString stringWithFormat:
@"%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x",
result[0], result[1], result[2], result[3],
result[4], result[5], result[6], result[7],
...
How to validate an email address in JavaScript
...b"@gmail.com, _@gmail.com, 1@gmail.com , 1_example@something.gmail.com are all valid, but Gmail will never allow any of these email addresses. You should do this by accepting the email address and sending an email message to that email address, with a code/link the user must visit to confirm validit...