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Detecting an undefined object property
...
@Zack Your tests for isNullorUndefined did not consider the case where you call isNullOrUndefined(f) and f is undeclared (i.e. where there is no "var f" declaration).
– pnkfelix
Feb 15 '13 at 15:08...
How to get a complete list of object's methods and attributes?
...en to go for its __bases__:
# code borrowed from the rlcompleter module
# tested under Python 2.6 ( sys.version = '2.6.5 (r265:79063, Apr 16 2010, 13:09:56) \n[GCC 4.4.3]' )
# or: from rlcompleter import get_class_members
def get_class_members(klass):
ret = dir(klass)
if hasattr(klass,'__b...
Importing from builtin library when module with same name exists
...
Works like a charm... Used this to test while developing a library, so that my tests were always using the developing version and not the published (and installed) one. In windows 10 i had to write the path to my module like this: file_path=r"C:\Users\My Use...
Is it possible to figure out the parameter type and return type of a lambda?
...e element of a tuple
// composed of those arguments.
};
};
// test code below:
int main()
{
auto lambda = [](int i) { return long(i*10); };
typedef function_traits<decltype(lambda)> traits;
static_assert(std::is_same<long, traits::result_type>::value, "err");
...
How do I provide custom cast support for my class?
...t from that example, using the explicit method, if you do:
string name = "Test";
Role role = (Role) name;
Then everything is fine; however, if you use:
object name = "Test";
Role role = (Role) name;
You will now get an InvalidCastException because string cannot be cast to Role, why, the compil...
How to get my IP address programmatically on iOS/macOS?
...s). Loopback addresses now returned, but its easy for you to uncomment the test to exclude them yourself.
EDIT2: (by some unknown person): Improved further March 13, 2015: In case the user uses a VPN (regardless over WiFi or Cellular), the previous code would have failed. Now, it works even with VP...
What is PECS (Producer Extends Consumer Super)?
...d when you both get and put.
Example in Java:
class Super {
Object testCoVariance(){ return null;} //Covariance of return types in the subtype.
void testContraVariance(Object parameter){} // Contravariance of method arguments in the subtype.
}
class Sub extends Super {
@Override
...
What is the difference between NaN and None?
...nswer the second question:
You should be using pd.isnull and pd.notnull to test for missing data (NaN).
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Python : List of dict, if exists increment a dict value, if not append a new dict
...urls)
If you really need to do it the way you showed, the easiest and fastest way would be to use any one of these three examples, and then build the one you need.
from collections import defaultdict # available in Python 2.5 and newer
urls_d = defaultdict(int)
for url in list_of_urls:
urls...
What are dictionary view objects?
...ike", in that they don't support indexing, so what you can do with them is test for membership and iterate over them (because keys are hashable and unique, the keys and items views are more "set-like" in that they don't contain duplicates).
You can store them and use them multiple times, like the li...