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Behaviour of increment and decrement operators in Python
...e applied on a variable (like ++count ). It compiles, but it does not actually change the value of the variable!
9 Answers...
Why use Abstract Base Classes in Python?
...emented classes.
Long version
There is a contract between a class and its callers. The class promises to do certain things and have certain properties.
There are different levels to the contract.
At a very low level, the contract might include the name of a method or its number of parameters.
In a s...
No output to console from a WPF application?
...
You'll have to create a Console window manually before you actually call any Console.Write methods. That will init the Console to work properly without changing the project type (which for WPF application won't work).
Here's a complete source code example, of how a C...
What is a singleton in C#?
...
A singleton is a class which only allows one instance of itself to be created - and gives simple, easy access to said instance. The singleton premise is a pattern across software development.
There is a C# implementation "Implementing the Singleton Pattern i...
How can jQuery deferred be used?
... // or may not have been retrieved using an
// XHR request.
});
Basically, if the value has already been requested once before it's returned immediately from the cache. Otherwise, an AJAX request fetches the data and adds it to the cache. The $.when/.then doesn't care about any of this; all ...
__FILE__ macro shows full path
....com/pipermail/cmake/2013-January/053117.html
I'm copying the tip so it's all on this page:
set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -D__FILENAME__='\"$(subst
${CMAKE_SOURCE_DIR}/,,$(abspath $<))\"'")
If you're using GNU make, I see no reason you couldn't extend this to your own makefiles. ...
What does -D_XOPEN_SOURCE do/mean?
...ch one you need (if any) by looking at the man page for each function you call.
For example, man strdup says:
Feature Test Macro Requirements for glibc (see feature_test_macros(7)):
strdup(): _SVID_SOURCE || _BSD_SOURCE || _XOPEN_SOURCE >= 500
strndup(), strdupa(), strndupa():...
Is it alright to use target=“_blank” in HTML5?
I recall reading somewhere that in HTML5 it was no longer okay to use target="_blank" in HTML5, but I can't find it now.
...
Multiple commands in gdb separated by some sort of delimiter ';'?
...rinted a backtrace, but it doesn't.
You can accomplish the same thing by calling into the Python interpreter.
python import gdb ; print(gdb.execute("s")) ; print(gdb.execute("bt"))
It's possible to wrap this up into a dedicated command, here called "cmds", backed by a python definition.
Here's a...
How to save an HTML5 Canvas as an image on a server?
I'm working on a generative art project where I would like to allow users to save the resulting images from an algorithm. The general idea is:
...