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Can a variable number of arguments be passed to a function?
...able to pass any number of arguments.
def manyArgs(*arg):
print "I was called with", len(arg), "arguments:", arg
>>> manyArgs(1)
I was called with 1 arguments: (1,)
>>> manyArgs(1, 2, 3)
I was called with 3 arguments: (1, 2, 3)
As you can see, Python will unpack the arguments...
What exactly is nullptr?
...constant can be converted to std::nullptr_t. The opposite direction is not allowed. This allows overloading a function for both pointers and integers, and passing nullptr to select the pointer version. Passing NULL or 0 would confusingly select the int version.
A cast of nullptr_t to an integral ty...
Immutability of Strings in Java
...t, and changing a reference. s2 still points to the same object as we initially set s1 to point to. Setting s1 to "Help!" only changes the reference, while the String object it originally referred to remains unchanged.
If strings were mutable, we could do something like this:
String s1 = "Hello";
St...
Find an item in List by LINQ?
Here I have a simple example to find an item in a list of strings. Normally I use for loop or anonymous delegate to do it like this:
...
In Django, how do I check if a user is in a certain group?
...add(group) # user is now in the "Editor" group
then user.groups.all() returns [<Group: Editor>].
Alternatively, and more directly, you can check if a a user is in a group by:
if django_user.groups.filter(name = groupname).exists():
...
Note that groupname can also be the ac...
Where does gcc look for C and C++ header files?
...stem header.
If you run gcc in verbose mode on such a source, it will list all the system include locations as it looks for the bogus header.
$ echo "#include <bogus.h>" > t.c; gcc -v t.c; rm t.c
[..]
#include "..." search starts here:
#include <...> search starts here:
/usr/local...
Putting git hooks into repository
...
I generally agree with Scytale, with a couple additional suggestions, enough that it's worth a separate answer.
First, you should write a script which creates the appropriate symlinks, especially if these hooks are about enforcing ...
Create a tag in a GitHub repository
...m the official Linux Kernel Git documentation for git push:
--tags
All refs under refs/tags are pushed, in addition to refspecs explicitly listed on the command line.
Or if you just want to push a single tag:
git push origin <tag>
See also my answer to How do you push a tag to a r...
Why do you need explicitly have the “self” argument in a Python method?
... to make things like this explicit rather than based on a rule.
Additionally, since nothing is implied or assumed, parts of the implementation are exposed. self.__class__, self.__dict__ and other "internal" structures are available in an obvious way.
...
CSS styling in Django forms
...ling, if you need an unique identifier its better to use id. Second its usually the template side's responsobilty to do exaclty this, Esspecially if you are going to access this class via frontend methods (js, css). I didn't say your answer is wrong. In my opinion its just bad practice (esspecially ...