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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")
...
Installed Ruby 1.9.3 with RVM but command line doesn't show ruby -v
... what do you do if env has a lot of rvm stuff in it still? like rvm_dump_environment_flag=0 etc...
– jcollum
Apr 22 '12 at 21:28
5
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How do I cast a variable in Scala?
...
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...
How to split a long regular expression into multiple lines in JavaScript?
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You could convert it to a string and create the expression by calling new RegExp():
var myRE = new RegExp (['^(([^<>()[\]\\.,;:\\s@\"]+(\\.[^<>(),[\]\\.,;:\\s@\"]+)*)',
'|(\\".+\\"))@((\\[[0-9]{1,3}\\.[0-9]{1,3}\\.[0-9]{1,3}\\.',
...
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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Is it possible to use 'else' in a list comprehension? [duplicate]
..., 2, 3]
So for your example,
table = ''.join(chr(index) if index in ords_to_keep else replace_with
for index in xrange(15))
share
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improve this answer
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How to check for valid email address? [duplicate]
...ere is no point. Even if you can verify that the email address is syntactically valid, you'll still need to check that it was not mistyped, and that it actually goes to the person you think it does. The only way to do that is to send them an email and have them click a link to verify.
Therefore, a ...
Passing arguments to C# generic new() of templated type
...tion you must constrain it with the "new" flag.
public static string GetAllItems<T>(...) where T : new()
However that will only work when you want to call the constructor which has no parameters. Not the case here. Instead you'll have to provide another parameter which allows for the cr...
Find the index of a dict within a list, by matching the dict's value
...as readable or Pythonic is @Emile's answer. Because the intention is not really to create a generator (and using next() for this seems weird to me), the aim is just to get the index. Also, this raises StopIteration, whereas the Python lst.index() method raises ValueError.
– Ben...
How to get Bitmap from an Uri?
...}
catch (Exception e)
{
e.printStackTrace();
}
finally {
if (bis != null)
{
try
{
bis.close();
}
catch (IOException e)
{
e.printStackTrace();
}
...
