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Can PostgreSQL index array columns?
... to this question in the documentation. If a column is an array type, will all the entered values be individually indexed?
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How to call a Parent Class's method from Child Class in Python?
...P was asking how to do it without explicitly naming the superclass at the call site (Bar, in this case).
– Adam Rosenfield
Apr 30 '09 at 2:13
8
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How can I represent an 'Enum' in Python?
...y3, e.g. you'll need __order__ in python 2).
To use enum34, do $ pip install enum34
To use aenum, do $ pip install aenum
Installing enum (no numbers) will install a completely different and incompatible version.
from enum import Enum # for enum34, or the stdlib version
# from aenum import...
How does type Dynamic work and how to use it?
...
Scalas type Dynamic allows you to call methods on objects that don't exist or in other words it is a replica of "method missing" in dynamic languages.
It is correct, scala.Dynamic doesn't have any members, it is just a marker interface - the co...
Checking if a double (or float) is NaN in C++
...nly if f is NaN.
Note that, as some comments below have pointed out, not all compilers respect this when optimizing code.
For any compiler which claims to use IEEE floating point, this trick should work. But I can't guarantee that it will work in practice. Check with your compiler, if in doubt.
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How do I pass values to the constructor on my wcf service?
... How can I use it for self hosting? I receive an exception after calling to CreateServiceHost. I can only call to the protected method public override ServiceHostBase CreateServiceHost(string constructorString, Uri[] baseAddresses); The exception is The exception message was: 'ServiceHostF...
Are there legitimate uses for JavaScript's “with” statement?
...ous as to how I might make effective use of with , while avoiding its pitfalls.
31 Answers
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Syntax Error: Not a Chance
...ng blocks by braces instead of indentation will never be implemented.
Normally, imports from the special __future__ module enable features that are backwards-incompatible, such as the print() function, or true division.
So the line from __future__ import braces is taken to mean you want to enable ...
What does 'super' do in Python?
...
What's the difference?
SomeBaseClass.__init__(self)
means to call SomeBaseClass's __init__. while
super(Child, self).__init__()
means to call a bound __init__ from the parent class that follows Child in the instance's Method Resolution Order (MRO).
If the instance is a subclass of ...
sql “LIKE” equivalent in django query
...s. I have made the lookup into a Django-like-lookup application. After installing it the __like lookup with the % and _ wildcards will be enabled.
All the necessary code in the application is:
from django.db.models import Lookup
from django.db.models.fields import Field
@Field.register_lookup
cl...