Using Python's built-in defaultdict we can easily define a tree data structure:
def tree(): return defaultdict(tree)
That's it!
Using Python's built-in defaultdict we can easily define a tree data structure:
def tree(): return defaultdict(tree)
That's it!
How do you send information between clients and servers? What format should that information be in? What happens when the server changes the format, but the client has not been updated yet? What happens when the server changes the format, but the database cannot be updated?
These are difficult questions. It is not just about picking a format, but rather picking a format that can evolve as your application evolves.
By now there are many approaches to communicating between client and server. These approaches tend to be known within specific companies and language communities, but the techniques do not cross borders. I will outline JSON, ProtoBuf, and GraphQL here so we can learn from them all.
/* Exercise: Loops and Functions #43 */ | |
package main | |
import ( | |
"fmt" | |
"math" | |
) | |
func Sqrt(x float64) float64 { | |
z := float64(2.) |
Simply put, destructuring in Clojure is a way extract values from a datastructure and bind them to symbols, without having to explicitly traverse the datstructure. It allows for elegant and concise Clojure code.
2015-01-29 Unofficial Relay FAQ
Compilation of questions and answers about Relay from React.js Conf.
Disclaimer: I work on Relay at Facebook. Relay is a complex system on which we're iterating aggressively. I'll do my best here to provide accurate, useful answers, but the details are subject to change. I may also be wrong. Feedback and additional questions are welcome.
Relay is a new framework from Facebook that provides data-fetching functionality for React applications. It was announced at React.js Conf (January 2015).
echo 'export PATH=$HOME/local/bin:$PATH' >> ~/.bashrc | |
. ~/.bashrc | |
mkdir ~/local | |
mkdir ~/node-latest-install | |
cd ~/node-latest-install | |
curl http://nodejs.org/dist/node-latest.tar.gz | tar xz --strip-components=1 | |
./configure --prefix=~/local | |
make install # ok, fine, this step probably takes more than 30 seconds... | |
curl https://www.npmjs.org/install.sh | sh |
import yaml | |
import yaml.constructor | |
try: | |
# included in standard lib from Python 2.7 | |
from collections import OrderedDict | |
except ImportError: | |
# try importing the backported drop-in replacement | |
# it's available on PyPI | |
from ordereddict import OrderedDict |
from MySQLdb.cursors import SSDictCursor | |
def iterate_query(query, connection, arraysize=1): | |
c = connection.cursor(cursorclass=SSDictCursor) | |
c.execute(query) | |
while True: | |
nextrows = c.fetchmany(arraysize) | |
if not nextrows: | |
break |