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Why do we need virtual functions in C++?
...t."
So far so good, right? Animals eat generic food, cats eat rats, all without virtual.
Let's change it a little now so that eat() is called via an intermediate function (a trivial function just for this example):
// This can go at the top of the main.cpp file
void func(Animal *xyz) { xyz->e...
How can I get the client's IP address in ASP.NET MVC?
...answer is to use the HttpRequest.UserHostAddress property.
Example: From within a Controller:
using System;
using System.Web.Mvc;
namespace Mvc.Controllers
{
public class HomeController : ClientController
{
public ActionResult Index()
{
string ip = Request.User...
C99 stdint.h header and MS Visual Studio
...ey have their reasons, but does anyone know where I can download a copy? Without this header I have no definitions for useful types such as uint32_t, etc.
...
Get all related Django model objects
... getattr(a, link).all()
for object in objects:
# do something with related object instance
I spent a while trying to figure this out so I could implement a kind of "Observer Pattern" on
one of my models. Hope it's helpful.
Django 1.8+
Use _meta.get_fields(): https://docs.djangoprojec...
Placeholder in UITextView
My application uses an UITextView . Now I want the UITextView to have a placeholder similar to the one you can set for an UITextField .
...
Removing duplicate objects with Underscore for Javascript
...5},{a:2},{a:3},{a:4},{a:3},{a:2}];
var uniqueList = _.uniq(list, function(item, key, a) {
return item.a;
});
// uniqueList = [Object {a=1, b=5}, Object {a=2}, Object {a=3}, Object {a=4}]
Notes:
Callback return value used for comparison
First comparison object with unique return value used...
Stop pip from failing on single package when installing with requirements.txt
...
Running each line with pip install may be a workaround.
cat requirements.txt | xargs -n 1 pip install
Note: -a parameter is not available under MacOS, so old cat is more portable.
...
How do I calculate the date in JavaScript three months prior to today?
... that one month ago means the same day of the month on the previous month citation needed. But more than half the time, that is 31 days ago, not 30. And if today is the 31st of the month (and it isn't August or Decemeber), that day of the month doesn't exist in the previous month.
Interestingly, ...
Capturing Groups From a Grep RegEx
I've got this little script in sh (Mac OSX 10.6) to look through an array of files. Google has stopped being helpful at this point:
...
How do I print the type or class of a variable in Swift?
...the examples below to the new Swift 2.0 syntax (e.g. println was replaced with print, toString() is now String()).
From the Xcode 6.3 release notes:
@nschum points out in the comments that the Xcode 6.3 release notes show another way:
Type values now print as the full demangled type name when ...