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How to query SOLR for empty fields?
...ough the SolrQuerySyntax page says -id:[* TO *], only -id:["" TO *] worked for me on solr 1.4.
– Jonathan Tran
Dec 14 '10 at 5:35
1
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Abstract classes in Swift Language
...weekly
Notice that this is providing "abstract class" like features even for structs, but classes can also implement the same protocol.
Also notice that every class or struct that implements the Employee protocol will have to declare the annualSalary property again.
Most importantly, notice that...
django: BooleanField, how to set the default value to true?
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If you're just using a vanilla form (not a ModelForm), you can set a Field initial value ( https://docs.djangoproject.com/en/2.2/ref/forms/fields/#django.forms.Field.initial ) like
class MyForm(forms.Form):
my_field = forms.BooleanField(initial=True)
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What is the difference between a field and a property?
...her) - which is a shorthand syntax
// used to generate a private field for you
public int AnotherProperty{get;set;}
}
@Kent points out that Properties are not required to encapsulate fields, they could do a calculation on other fields, or serve other purposes.
@GSS points out that you ca...
How to create a zip archive of a directory in Python?
...s
import zipfile
def zipdir(path, ziph):
# ziph is zipfile handle
for root, dirs, files in os.walk(path):
for file in files:
ziph.write(os.path.join(root, file))
if __name__ == '__main__':
zipf = zipfile.ZipFile('Python.zip', 'w', zipfile.ZIP_DEFLATED)
zipdir('t...
django : using select_related and get_object_or_404 together
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Thanks for contributing an answer to Stack Overflow!Please be sure to answer the question. Provide details and share your research!But avoid …Asking for help, clarification, or responding to other answers.Making statements based o...
How are GCC and g++ bootstrapped?
This has been bugging me for a while. How do GCC and g++ compile themselves?
1 Answer
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How to use a custom comparison function in Python 3?
...ke the recipe give me a workaround, but I think I am going to lose some performance by passing all the comparison operators < > = to middle man, since my original custom sort is written in C , it had around 1/2x speed of default sort.
– YOU
Mar 28 '10 at...
How to optimize for-comprehensions and loops in Scala?
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The problem in this particular case is that you return from within the for-expression. That in turn gets translated into a throw of a NonLocalReturnException, which is caught at the enclosing method. The optimizer can eliminate the foreach but cannot yet eliminate the throw/catch. And throw/catc...
Reverse a string in Python
There is no built in reverse function for Python's str object. What is the best way of implementing this method?
28 Ans...