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Rails :include vs. :joins
... what I understood (with examples :))
Consider this scenario:
A User has_many comments and a comment belongs_to a User.
The User model has the following attributes: Name(string), Age(integer). The Comment model has the following attributes:Content, user_id. For a comment a user_id can be null.
...
C++ Redefinition Header Files (winsock2.h)
...list that <windows.h> is included after <winsock2.h> or define _WINSOCKAPI_ first:
#define _WINSOCKAPI_ // stops windows.h including winsock.h
#include <windows.h>
// ...
#include "MyClass.h" // Which includes <winsock2.h>
See also this.
...
Is there a way to use SVG as content in a pseudo element :before or :after
...
<div class="author_">Lord Byron</div>
.author_ { font-family: 'Playfair Display', serif; font-size: 1.25em; font-weight: 700;letter-spacing: 0.25em; font-style: italic;
position:relative;
margin-top: -0.5em;
color: bla...
When would anyone use a union? Is it a remnant from the C-only days?
...For example, let's say you want to create your own Variant type:
struct my_variant_t {
int type;
union {
char char_value;
short short_value;
int int_value;
long long_value;
float float_value;
double double_value;
void* ptr_value;
}...
How to make a SPA SEO crawlable?
..."!">. This tag will make google's bot transform the URL to www.xyz.com?_escaped_fragment_= which we'll see later.
The 'about' route is just an example to a link to other 'pages' you may want on your web application.
Now, the tricky part is that there is no 'category' route, and there may be many...
VIM Replace word with contents of paste buffer?
...th the change command to go anywhere, you can use the black hole register "_: "_cw. Then once in insert mode, you can hit ctrl-R followed by the register you want (probably ") to put in the contents of that register.
"* - selection register (middle-button paste)
"+ - clipboard register (probably a...
Removing colors from output
...all conceivable ANSI escape sequences:
./somescript | sed 's/\x1B[@A-Z\\\]^_]\|\x1B\[[0-9:;<=>?]*[-!"#$%&'"'"'()*+,.\/]*[][\\@A-Z^_`a-z{|}~]//g'
(and if you have @edi9999's SI problem, add | sed "s/\x0f//g" to the end; this works for any control char by replacing 0f with the hex of the u...
Uploading images using Node.js, Express, and Mongoose
...b.
// Expose modules in ./support for demo purposes
require.paths.unshift(__dirname + '/../../support');
/**
* Module dependencies.
*/
var express = require('../../lib/express')
, form = require('connect-form');
var app = express.createServer(
// connect-form (http://github.com/visionmedia...
How to debug a Flask app
...e browser when there is an error. To run in development mode, set the FLASK_ENV=development environment variable then use the flask run command (remember to point FLASK_APP to your app as well).
For Linux, Mac, Linux Subsystem for Windows, Git Bash on Windows, etc.:
export FLASK_APP=myapp
export F...
How can I check if an ip is in a network in Python?
...otted quad string to long integer"
return struct.unpack('L',socket.inet_aton(ip))[0]
def networkMask(ip,bits):
"Convert a network address to a long integer"
return dottedQuadToNum(ip) & makeMask(bits)
def addressInNetwork(ip,net):
"Is an address in a network"
return ip &...