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Can anyone explain python's relative imports?
...from package "sub". start.py is not itself in a package even if there is a __init__.py present.
You would need to start your program from one directory over parent.py:
./start.py
./pkg/__init__.py
./pkg/parent.py
./pkg/sub/__init__.py
./pkg/sub/relative.py
With start.py:
import pkg.sub.relativ...
Python mysqldb: Library not loaded: libmysqlclient.18.dylib
... a slightly different spot: sudo ln -s /usr/local/mysql-5.5.29-osx10.6-x86_64/lib/libmysqlclient.18.dylib /usr/lib/libmysqlclient.18.dylib
– Matt
Apr 2 '14 at 16:35
...
How to convert CFStringRef to NSString?
...e using ARC, the new casting syntax is as follows:
NSString *aNSString = (__bridge NSString *)aCFString;
works as well. The key thing to note is that CoreFoundation will often return objects with +1 reference counts, meaning that they need to be released (all CF[Type]Create format functions do th...
(this == null) in C#!
... {
base..ctor(new Func<string>(Program.Derived.<.ctor>b__0));
return;
}
[CompilerGenerated]
private static string <.ctor>b__0()
{
string CS$1$0000;
CS$1$0000 = CS$1$0000.CheckNull();
Label_0009:
return CS$1$0000;
}
...
What is the most effective way for float and double comparison?
...all depends on context and the expected size of a and b.
BTW, std::numeric_limits<double>::epsilon() is the "machine epsilon". It is the difference between 1.0 and the next value representable by a double. I guess that it could be used in the compare function but only if the expected values a...
Static files in Flask - robot.txt, sitemap.xml (mod_wsgi)
...
The best way is to set static_url_path to root url
from flask import Flask
app = Flask(__name__, static_folder='static', static_url_path='')
share
|
...
How to throw std::exceptions with variable messages?
...atter & operator << (const Type & value)
{
stream_ << value;
return *this;
}
std::string str() const { return stream_.str(); }
operator std::string () const { return stream_.str(); }
enum ConvertToString
{
to_str
};...
Dictionaries and default values
...collections import defaultdict
a = defaultdict(lambda: "default", key="some_value")
a["blabla"] => "default"
a["key"] => "some_value"
You can pass any ordinary function instead of lambda:
from collections import defaultdict
def a():
return 4
b = defaultdict(a, key="some_value")
b['absent...
Getter and Setter declaration in .NET [duplicate]
...ed property. When the need arises you can expand your property to:
string _myProperty;
public string MyProperty
{
get { return _myProperty; }
set { _myProperty = value; }
}
Now you can add code that validates the value in your setter:
set
{
if (string.IsNullOrWhiteSpace(value))
...
Referring to the null object in Python
...t;> NoneType = type(None)
>>> id(None)
10748000
>>> my_none = NoneType()
>>> id(my_none)
10748000
>>> another_none = NoneType()
>>> id(another_none)
10748000
>>> def function_that_does_nothing(): pass
>>> return_value = function_that_...