non

What is the appeal of dynamically-typed languages?

Kris Nuttycombe asks:

I genuinely wish I understood the appeal of unityped languages better. Can someone who really knows both well-typed and unityped explain?

I think the terms well-typed and unityped are a bit of question-begging here (you might as well say good-typed versus bad-typed), so instead I will say statically-typed and dynamically-typed.

I'm going to approach this article using Scala to stand-in for static typing and Python for dynamic typing. I feel like I am credibly proficient both languages: I don't currently write a lot of Python, but I still have affection for the language, and have probably written hundreds of thousands of lines of Python code over the years.

nolanlawson

Convert a Cordova/Ionic project to a Crosswalk project

Converts an existing Cordova/Ionic project to a Crosswalk project. When the script is done running, you should have a fat 40MB APK file in platforms/android/ant-build.

This assumes you have the following already installed: cordova, ant, android, and that your ANDROID_HOME is set to point to the Android SDK.

This will work on both x86 and ARM. If you want to build two separate APKs so that they're smaller, then modify the script; the script at least shows how it works.

Step 1: download the "Cordova Android" libraries from the Crosswalk downloads page. You don't need anything except for the "Cordova Android" ones.

tito

'''
Bluetooth/Pyjnius example
=========================

This was used to send some bytes to an arduino via bluetooth.
The app must have BLUETOOTH and BLUETOOTH_ADMIN permissions (well, i didn't
tested without BLUETOOTH_ADMIN, maybe it works.)

Connect your device to your phone, via the bluetooth menu. After the
pairing is done, you'll be able to use it in the app.

jboner

Latency Comparison Numbers (~2012)
----------------------------------
L1 cache reference                           0.5 ns
Branch mispredict                            5   ns
L2 cache reference                           7   ns                      14x L1 cache
Mutex lock/unlock                           25   ns
Main memory reference                      100   ns                      20x L2 cache, 200x L1 cache
Compress 1K bytes with Zippy             3,000   ns        3 us
Send 1K bytes over 1 Gbps network       10,000   ns       10 us
Read 4K randomly from SSD*             150,000   ns      150 us          ~1GB/sec SSD

RedBeard0531

// derived from http://en.wikipedia.org/wiki/Algorithms_for_calculating_variance#Parallel_algorithm

function map() {
    emit(1, // Or put a GROUP BY key here
         {sum: this.value, // the field you want stats for
          min: this.value,
          max: this.value,
          count:1,
          diff: 0, // M2,n:  sum((val-mean)^2)
    });

pamelafox

countries = [
{'timezones': ['Europe/Andorra'], 'code': 'AD', 'continent': 'Europe', 'name': 'Andorra', 'capital': 'Andorra la Vella'},
{'timezones': ['Asia/Kabul'], 'code': 'AF', 'continent': 'Asia', 'name': 'Afghanistan', 'capital': 'Kabul'},
{'timezones': ['America/Antigua'], 'code': 'AG', 'continent': 'North America', 'name': 'Antigua and Barbuda', 'capital': "St. John's"},
{'timezones': ['Europe/Tirane'], 'code': 'AL', 'continent': 'Europe', 'name': 'Albania', 'capital': 'Tirana'},
{'timezones': ['Asia/Yerevan'], 'code': 'AM', 'continent': 'Asia', 'name': 'Armenia', 'capital': 'Yerevan'},
{'timezones': ['Africa/Luanda'], 'code': 'AO', 'continent': 'Africa', 'name': 'Angola', 'capital': 'Luanda'},
{'timezones': ['America/Argentina/Buenos_Aires', 'America/Argentina/Cordoba', 'America/Argentina/Jujuy', 'America/Argentina/Tucuman', 'America/Argentina/Catamarca', 'America/Argentina/La_Rioja', 'America/Argentina/San_Juan', 'America/Argentina/Mendoza', 'America/Argentina/Rio_Gallegos', 'America/Argentina/Ushuai