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Unique BooleanField value in Django?

... save method of the model and if you've set the boolean to True, make sure all others are set to False. from django.db import transaction class Character(models.Model): name = models.CharField(max_length=255) is_the_chosen_one = models.BooleanField() def save(self, *args, **kwargs): ...
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Django. Override save for model

...self._image_changed = True # Or put whole logic in here small = rescale_image(self.image,width=100,height=100) self.image_small=SimpleUploadedFile(name,small_pic) def get_image(self): return self._image image = property(get_image, set_image) # this is ...
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git diff two files on same branch, same commit

... but the fact that he mentions BeyondCompare implies that he's not specifically looking for a git diff but simply an easy to read diff. Also the fact he accepted my answer as what he was looking for also indicates that it does in fact answer it. – JaredMcAteer ...
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Is there a way to chain multiple value converters in XAML?

... @DLeh This is not really elegant as is doesn't work. It provides all converters with final target type instead of correct target type... – Aleksandar Toplek Sep 7 '15 at 10:53 ...
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Is null an Object?

...is only an object if it is equal to or subclasses java.lang.Object. Practically - yes. You can't create a class that is not a subclass of java.lang.Object, but I never thought about it from a more philosophical point of view – Andreas Dolk Dec 12 '09 at 22:23 ...
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How to define an enum with string value?

... @ShaunLuttin: enums are just "named numbers" - so a string enum really doesn't fit in with that model at all. – Jon Skeet Aug 12 '17 at 6:55  |  ...
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Convert array of strings to List

...000/svg\"\u003e\u003cpath d=\"M46.1709 9.17788C46.1709 8.26454 46.2665 7.94324 47.1084 7.58816C47.4091 7.46349 47.7169 7.36433 48.0099 7.26993C48.9099 6.97997 49.672 6.73443 49.672 5.93063C49.672 5.22043 48.9832 4.61182 48.1414 4.61182C47.4335 4.61182 46.7256 4.91628 46.0943 5.50789C45.7307 4.9328 4...
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ActiveRecord OR query

How do you do an OR query in Rails 3 ActiveRecord. All the examples I find just have AND queries. 14 Answers ...
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Curious null-coalescing operator custom implicit conversion behaviour

...l; there's no need to check it for null a second time just because we are calling a lifted conversion operator". We'd them optimize it away to just new int?(op_Implicit(temp2.Value)) My guess is that we are somewhere caching the fact that the optimized form of (int?)Foo() is new int?(op_implici...
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Java optional parameters

... varargs could do that (in a way). Other than that, all variables in the declaration of the method must be supplied. If you want a variable to be optional, you can overload the method using a signature which doesn't require the parameter. private boolean defaultOptionalFlagVa...