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Create a menu Bar in WPF?
...nel>
<Menu DockPanel.Dock="Top">
<MenuItem Header="_File">
<MenuItem Header="_Open"/>
<MenuItem Header="_Close"/>
<MenuItem Header="_Save"/>
</MenuItem>
</Menu>
<StackPanel></StackPa...
Run a callback only if an attribute has changed in Rails
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Rails 5.1+
class Page < ActiveRecord::Base
before_save :do_something, if: :will_save_change_to_status_id?
private
def do_something
# ...
end
end
The commit that changed ActiveRecord::Dirty is here: https://github.com/rails/rails/commit/16ae3db5a5c6a08383b974ae...
How to loop through all the properties of a class?
...).
You don't need to specify BindingFlags.GetProperty, you use that when calling type.InvokeMember() to get the value of a property.
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Django admin: How to display a field that is marked as editable=False' in the model?
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+1. Especially if you don't plan to edit the field at all in Admin.
– Manoj Govindan
Oct 19 '10 at 16:05
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What is the best way to remove accents (normalize) in a Python unicode string?
I have a Unicode string in Python, and I would like to remove all the accents (diacritics).
8 Answers
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Linux command or script counting duplicated lines in a text file?
...3
}
or you can use a simple one-liner:
$ cat filename | python3 -c 'print(__import__("json").dumps(__import__("collections").Counter(map(str.strip, __import__("fileinput").input())), indent=2))'
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How can I use if/else in a dictionary comprehension?
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@Marcin's answer covers it all, but just in case someone wants to see an actual example, I add two below:
Let's say you have the following dictionary of sets
d = {'key1': {'a', 'b', 'c'}, 'key2': {'foo', 'bar'}, 'key3': {'so', 'sad'}}
and you want ...
How to Remove ReadOnly Attribute on File Using PowerShell?
...e here? As for Keith's answer, he's using PSCX. Not everyone has those installed and that's not really a case of PowerShell v1 vs. v2.
– Joey
Apr 22 '11 at 9:28
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Difference between Django's annotate and aggregate methods?
...rage_price': 34.35}
Returns a dictionary containing the average price of all books in the queryset.
Annotation
>>> q = Book.objects.annotate(num_authors=Count('authors'))
>>> q[0].num_authors
2
>>> q[1].num_authors
1
q is the queryset of books, but each book has been...
What is the maximum float in Python?
I think the maximum integer in python is available by calling sys.maxint .
3 Answers
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