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Forward declaration of nested types/classes in C++
...:Nested; // But this doesn't work.
My workaround was:
class IDontControl_Nested; // Forward reference to distinct name.
Later when I could use the full definition:
#include <idontcontrol.h>
// I defined the forward ref like this:
class IDontControl_Nested : public IDontControl::Nested
{...
Send and receive messages through NSNotificationCenter in Objective-C?
...
@implementation TestClass
- (void) dealloc
{
// If you don't remove yourself as an observer, the Notification Center
// will continue to try and send notification objects to the deallocated
// object.
[[NSNotificationCenter defaultCenter] removeO...
ASP.NET MVC 4 Custom Authorize Attribute with Permission Codes (without roles)
...e : AuthorizeAttribute, IAuthorizationFilter
{
private readonly string _claim;
public ClaimAuthorizeAttribute(string Claim)
{
_claim = Claim;
}
public void OnAuthorization(AuthorizationFilterContext context)
{
var user = context.HttpContext.User;
if(...
Getting individual colors from a color map in matplotlib
...You can do this with the code below, and the code in your question was actually very close to what you needed, all you have to do is call the cmap object you have.
import matplotlib
cmap = matplotlib.cm.get_cmap('Spectral')
rgba = cmap(0.5)
print(rgba) # (0.99807766255210428, 0.99923106502084169,...
Python Image Library fails with message “decoder JPEG not available” - PIL
...you are on 64bit or 32bit Ubuntu.
For Ubuntu x64:
sudo ln -s /usr/lib/x86_64-linux-gnu/libjpeg.so /usr/lib
sudo ln -s /usr/lib/x86_64-linux-gnu/libfreetype.so /usr/lib
sudo ln -s /usr/lib/x86_64-linux-gnu/libz.so /usr/lib
Or for Ubuntu 32bit:
sudo ln -s /usr/lib/i386-linux-gnu/libjpeg.so /usr/l...
Creating a config file in PHP
...ne simple but elegant way is to create a config.php file (or whatever you call it) that just returns an array:
<?php
return array(
'host' => 'localhost',
'username' => 'root',
);
And then:
$configs = include('config.php');
...
AngularJS sorting by property
...'s rows in the filter e.g. for(var objectKey in input) { input[objectKey]['_key'] = objectKey; array.push(input[objectKey]); } Like that we can use <div ng-repeat="value in object | orderObjectBy:'order'" ng-init="key = value['_key']">
– Nicolas Janel
Jul...
find() with nil when there are no records
...
Yes, just do:
Challenge.find_by_id(10)
For Rails 4 and 5:
Challenge.find_by(id: 10)
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byte[] to hex string [duplicate]
...
@Grungondola: It sounds strange that all other ways of converting bytes to a string would be so much slower. You weren't using += to concatenate the strings together, were you?
– Guffa
Nov 23 '15 at 22:29
...
How to call base.base.method()?
...Derived
{
public override void Say()
{
Console.WriteLine("Called from Special Derived.");
var ptr = typeof(Base).GetMethod("Say").MethodHandle.GetFunctionPointer();
var baseSay = (Action)Activator.CreateInstance(typeof(Action), this, ptr);
baseSay(...