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g++ undefined reference to typeinfo
...ill contain null-pointer most likely). However, nobody prohibits you from calling this pure virtual function in a non-virtual manner, i.e. by using a fully-qualified name. In this case the linker will look for the body, and you will have to define the function. And yes, you can define a body for a p...
Python: Why is functools.partial necessary?
...rticular) appear to like lambda just fine – I say "most", definitely not all, because Guido and I assuredly are among those "familiar with" (etc) yet think of lambda as an eyesore anomaly in Python...
He was repentant of ever having accepted it into Python whereas planned to remove it from Python ...
Redirecting Output from within Batch file
... good and fast way that only opens and positions the file once
@echo off
call :sub >output.txt
exit /b
:sub
command1
command2
...
commandN
Edit 2020-04-17
Every now and then you may want to repeatedly write to two or more files. You might also want different messages on the screen. It is sti...
How to get an object's properties in JavaScript / jQuery?
...Script's native for in loop:
var obj = {
foo: 'bar',
base: 'ball'
};
for(var key in obj) {
alert('key: ' + key + '\n' + 'value: ' + obj[key]);
}
or using jQuery's .each() method:
$.each(obj, function(key, element) {
alert('key: ' + key + '\n' + 'value: ' + element);
});
W...
Building a minimal plugin architecture in Python
...
Mine is, basically, a directory called "plugins" which the main app can poll and then use imp.load_module to pick up files, look for a well-known entry point possibly with module-level config params, and go from there. I use file-monitorin...
How to remove constraints from my MySQL table?
...
Postgres, MSSQL, and Oracle all have alter table .. drop constraint. MySQL is the odd one out, it seems.
– Jared Beck
Mar 23 '15 at 23:48
...
UITableViewCell, show delete button on swipe
...
During startup in (-viewDidLoad or in storyboard) do:
self.tableView.allowsMultipleSelectionDuringEditing = NO;
Override to support conditional editing of the table view. This only needs to be implemented if you are going to be returning NO for some items. By default, all items are editable....
Generate random numbers using C++11 random library
... functions and why not to use rand(). In it, he included a slide that basically solves your question. I've copied the code from that slide below.
You can see his full talk here: http://channel9.msdn.com/Events/GoingNative/2013/rand-Considered-Harmful
#include <random>
#include <iostream&g...
Why does Ruby 1.9.2 remove “.” from LOAD_PATH, and what's the alternative?
... LOAD_PATH , so this broke them (they reported "no such file to load" for all require statements that based off the project path). Was there a particular justification for doing this?
...
Bad class file magic or version
...K section, when you add an Android SDK you should provide the Java SDK and all my Android SDKs uses Java 8 as SDK so it create the class files with the wrong version even if the Project level is 1.7 (i don't know why, i supposed that everything was choosed by Project level).
Now i changed the SDK (...