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Creating an abstract class in Objective-C
I'm originally a Java programmer who now works with Objective-C. I'd like to create an abstract class, but that doesn't appear to be possible in Objective-C. Is this possible?
...
super() fails with error: TypeError “argument 1 must be type, not classobj” when parent does not inh
...ss. Change it like so:
class B(object):
and it will work.
super() and all subclass/superclass stuff only works with new-style classes. I recommend you get in the habit of always typing that (object) on any class definition to make sure it is a new-style class.
Old-style classes (also known as...
How to wrap text around an image using HTML/CSS
...p: 70px;
display: inline-block;
}
<div class="oval"><span>PHP</span>
</div>
<p>Lorem Ipsum is simply dummy text of the printing and typesetting industry. Lorem Ipsum has been the industry's standard dummy text ever since the 1500s, when an unknown printer took a ...
PowerShell script to return versions of .NET Framework on a machine?
...t). It also outputs both Client and Full on 4.0 (if you have them both installed):
Get-ChildItem 'HKLM:\SOFTWARE\Microsoft\NET Framework Setup\NDP' -recurse |
Get-ItemProperty -name Version,Release -EA 0 |
Where { $_.PSChildName -match '^(?!S)\p{L}'} |
Select PSChildName, Version, Release
Based o...
Python: Tuples/dictionaries as keys, select, sort
...es and so on.
I'd like to organize them in a data structure in Python that allows for easy selection and sorting. My idea was to put them into a dictionary with tuples as keys, e.g.,
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Difference between shared objects (.so), static libraries (.a), and DLL's (.so)?
... and shared objects are just different terms for the same thing - Windows calls them DLLs, while on UNIX systems they're shared objects, with the general term - dynamically linked library - covering both (even the function to open a .so on UNIX is called dlopen() after 'dynamic library').
They are ...
Difference between reduce and foldLeft/fold in functional programming (particularly Scala and Scala
...t is both commutative and associative. This means the operation can be parallelized.
This distinction is very important for Big Data / MPP / distributed computing, and the entire reason why reduce even exists. The collection can be chopped up and the reduce can operate on each chunk, then the red...
Print current call stack from a method in Python code
In Python, how can I print the current call stack from within a method (for debugging purposes).
7 Answers
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How to list imported modules?
How to enumerate all imported modules?
9 Answers
9
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Creating a singleton in Python
...mple implementation:
class Singleton(type):
_instances = {}
def __call__(cls, *args, **kwargs):
if cls not in cls._instances:
cls._instances[cls] = super(Singleton, cls).__call__(*args, **kwargs)
return cls._instances[cls]
class Logger(object):
__meta...