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Add a reference column migration in Rails 4
...users and uploads tables and wish to add a new relationship between them.
All you need to do is: just generate a migration using the following command:
rails g migration AddUserToUploads user:references
Which will create a migration file as:
class AddUserToUploads < ActiveRecord::Migration
...
Shortest distance between a point and a line segment
...ode, in C++. It presumes a class 2D-vector class vec2 {float x,y;}, essentially, with operators to add, subract, scale, etc, and a distance and dot product function (i.e. x1 x2 + y1 y2).
float minimum_distance(vec2 v, vec2 w, vec2 p) {
// Return minimum distance between line segment vw and point ...
How to import the class within the same directory or sub directory?
I have a directory that stores all the .py files.
13 Answers
13
...
How to clone all remote branches in Git?
..., StackOverflow has grown quite a bit in terms of quality.
This "answer" really does not address the question at all. In fact, few of the top-voted answers do.
Here are two answers that will work as of git v2.28.0:
https://stackoverflow.com/a/4754797/430062
https://stackoverflow.com/a/7216269/43006...
Are strongly-typed functions as parameters possible in TypeScript?
...f the types of its argument and its return type. Here we specify that the callback parameter's type must be "function that accepts a number and returns type any":
class Foo {
save(callback: (n: number) => any) : void {
callback(42);
}
}
var foo = new Foo();
var strCallback = (re...
Super-simple example of C# observer/observable with delegates
...
The observer pattern is usually implemented with events.
Here's an example:
using System;
class Observable
{
public event EventHandler SomethingHappened;
public void DoSomething() =>
SomethingHappened?.Invoke(this, EventArgs.Empt...
Code Golf: Collatz Conjecture
...sp+0x04], 2
jne .usage
mov ebx, [esp+0x08]
push dword [ebx+0x04]
call atoi
add esp, 4
cmp eax, 0
je .usage
mov ebx, eax
push eax
push msg
.loop:
mov [esp+0x04], ebx
call printf
test ebx, 0x01
jz .even
.odd:
lea ebx, [1+ebx*2+ebx]
jmp .loop
.even:
shr ebx, 1
...
I lose my data when the container exits
...it. Try this:
sudo docker pull ubuntu
sudo docker run ubuntu apt-get install -y ping
Then get the container id using this command:
sudo docker ps -l
Commit changes to the container:
sudo docker commit <container_id> iman/ping
Then run the container:
sudo docker run iman/ping ping w...
Breaking up long strings on multiple lines in Ruby without stripping newlines
...
JessehzJessehz
4,32722 gold badges1212 silver badges1313 bronze badges
...
How can I run PowerShell with the .NET 4 runtime?
... that will change the .NET framework loaded systemwide, which will in turn allow PowerShell to use .NET 4.0 classes:
reg add hklm\software\microsoft\.netframework /v OnlyUseLatestCLR /t REG_DWORD /d 1
reg add hklm\software\wow6432node\microsoft\.netframework /v OnlyUseLatestCLR /t REG_DWORD /d 1
...
