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How to make an immutable object in Python?
...ter(1))
p = Point(2, 3)
p.x
# 2
p.y
# 3
Edit: If you want to get rid of indexing either, you can override __getitem__():
class Point(tuple):
__slots__ = []
def __new__(cls, x, y):
return tuple.__new__(cls, (x, y))
@property
def x(self):
return tuple.__getitem__(se...
Illegal mix of collations (utf8_unicode_ci,IMPLICIT) and (utf8_general_ci,IMPLICIT) for operation '=
...aka the COLLATE cast approach, can lead to potential bottleneck, cause any index defined on the column will not be used causing a full scan.
Even though I did not try out Option 3, my hunch is that it will suffer the same consequences of option 1 and 2.
Lastly, Option 4 is the best option for very...
How to tell if node.js is installed or not
...ory using mkdir NodeJs. Inside the NodeJs folder create a file using touch index.js. Open your index.js either using vi or in your favourite text editor. Type in console.log('Welcome to NodesJs.') and save it. Navigate back to your saved file and type node index.js. If you see Welcome to NodesJs. yo...
Pry: show me the stack
...personal_site/app/controllers/posts_controller.rb @ line 7 PostsController#index:
5: def index
6: @posts = Post.all
=> 7: binding.pry
8: end
[1] pry(#<PostsController>)> show-stack
Showing all accessible frames in stack (65 in total):
--
=> #0 index <PostsContr...
How to git-cherry-pick only changes to certain files?
...fications you do want
git add <path>
# make the work tree match the index
# (do this from the top level of the repo)
git checkout .
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Why are there two ways to unstage a file in Git?
...
git rm --cached is used to remove a file from the index. In the case where the file is already in the repo, git rm --cached will remove the file from the index, leaving it in the working directory and a commit will now remove it from the repo as well. Basically, after the co...
Loading basic HTML in Node.js
...ugh.
var http = require('http'),
fs = require('fs');
fs.readFile('./index.html', function (err, html) {
if (err) {
throw err;
}
http.createServer(function(request, response) {
response.writeHeader(200, {"Content-Type": "text/html"});
response.wr...
Can I set enum start value in Java?
...va to create a enum of sequential integers (similar to a C++ enum), for an index into an array or something, be to write: enum Ids { NAME(0), AGE(1), HEIGHT(2), WEIGHT(3); } Thank you, -bn
– bn.
Aug 13 '09 at 19:35
...
MySQL Conditional Insert
...s the insert instead of updating or inserting a row when you have a unique index on (user, item).
The query will look like this:
INSERT IGNORE INTO x_table(instance, user, item) VALUES (919191, 123, 456)
You can add the unique index with CREATE UNIQUE INDEX user_item ON x_table (user, item).
...
Why does UITableViewCell remain highlighted?
...
In your didSelectRowAtIndexPath you need to call deselectRowAtIndexPath to deselect the cell.
So whatever else you are doing in didSelectRowAtIndexPath you just have it call deselectRowAtIndexPath as well.
- (void)tableView:(UITableView *)tableV...