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django - query filter on manytomany is empty
In Django is there a way to filter on a manytomany field being empty or null.
2 Answers
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Calling static generic methods
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Or, as in my case: Foo.<E>createFoo(); Thank you :)
– fredoverflow
Mar 14 '11 at 11:37
7
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What are the rules for JavaScript's automatic semicolon insertion (ASI)?
...ents are affected by the automatic semicolon insertion (also known as ASI for brevity):
empty statement
var statement
expression statement
do-while statement
continue statement
break statement
return statement
throw statement
The concrete rules of ASI, are described in the specification §11.9.1 R...
How do you determine which backend is being used by matplotlib?
Either interactively, such as from within an Ipython session, or from within a script, how can you determine which backend is being used by matplotlib?
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How do I convert a string to a number in PHP?
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You don't typically need to do this, since PHP will coerce the type for you in most circumstances. For situations where you do want to explicitly convert the type, cast it:
$num = "3.14";
$int = (int)$num;
$float = (float)$num;
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Understanding the difference between __getattr__ and __getattribute__
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Some basics first.
With objects, you need to deal with its attributes. Ordinarily we do instance.attribute. Sometimes we need more control (when we do not know the name of the attribute in advance).
For example, instance.attribute would become getattr(instance, attribute_name). Using this mod...
.bashrc at ssh login
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this should work on any sane distro with Bash, thus all these comments are obsolete :)
– user529649
Jul 2 '12 at 2:09
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What is the MIME type for Markdown?
Does anyone know if there exists a MIME type for Markdown? I guess it is text/plain , but is there a more specific one?
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How to call shell commands from Ruby
...a shell, it typically calls /bin/sh, not Bash. Some Bash syntax is not supported by /bin/sh on all systems.
Here are ways to execute a shell script:
cmd = "echo 'hi'" # Sample string that can be used
Kernel#` , commonly called backticks – `cmd`
This is like many other languages, including Ba...
Can someone explain the HTML5 aria-* attribute?
I wanted to know what the aria-* attributes are used for. What values can they have, and are they defined values or can I create my own values?
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