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Correct way to use get_or_create?
...f the fields have to be included in defaults. In case CREATE event occurs, all the fields are taken into consideration.
It looks like you need to be returning into a tuple, instead of a single variable, do like this:
customer.source,created = Source.objects.get_or_create(name="Website")
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How do I cast a variable in Scala?
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The preferred technique is to use pattern matching. This allows you to gracefully handle the case that the value in question is not of the given type:
g match {
case g2: Graphics2D => g2
case _ => throw new ClassCastException
}
This block replicates the semantics of th...
Embedding SVG into ReactJS
...chbook.org/uri/2009/osb"``` from the svg tag, leaving only the xlmns. It's all about tag parsing apparently. Just in case, I've followed these steps as well: blog.logrocket.com/how-to-use-svgs-in-react
– Funder
Jul 8 at 22:47
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How do you test a public/private DSA keypair?
...ter/ssh
Note: My previous answer (in Mar 2018) no longer works with the latest releases of openssh. Previous answer: diff -qs <(ssh-keygen -yf ~/.ssh/id_rsa) <(cut -d ' ' -f 1,2 ~/.ssh/id_rsa.pub)
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warning: [options] bootstrap class path not set in conjunction with -source 1.5
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javac -source 1.7 -bootclasspath "$JAVA_HOME/jre/lib/rt.jar" Main.java
Tested on Ubuntu 14.04 for Oracle Java 7 and 8.
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How do you tell if caps lock is on using JavaScript?
...nput, turning on caps lock makes the led go red otherwise green. (Haven't tested on mac/linux)
NOTE: Both versions are working for me. Thanks for constructive inputs in the comments.
OLD VERSION: https://jsbin.com/mahenes/edit?js,output
Also, here is a modified version (can someone test on mac an...
How to detect unused methods and #import in Objective-C
...from actual executions. This is usually done in tandem with automated unit testing, but doesn't have to be.
This blog post is a decent introduction to unit testing and code coverage using Xcode. The section on gcov (which only works with code generated by GCC, by the way) explains how to get Xcode ...
How to perform runtime type checking in Dart?
...on, the is operator is defined on page 59 of the spec, section 10.30 'Type test'
– Duncan
Oct 11 '11 at 8:53
4
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Java FileOutputStream Create File if not exists
...oc), but it will create it if it can. To be sure you probably should first test that the file exists before you create the FileOutputStream (and create with createNewFile() if it doesn't):
File yourFile = new File("score.txt");
yourFile.createNewFile(); // if file already exists will do nothing
Fi...
When should assertions stay in production code? [closed]
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@jkschneider: unit tests are for testing things within the scope of the program's code. assertions are for ensuring that assumptions which the code is based on are actually true in reality, before the code continues processing under those assu...