Kozo Nishida kozo2

Moving to ES6 from CoffeeScript

I fell in love with CoffeeScript a couple of years ago. Javascript has always seemed something of an interesting curiosity to me and I was happy to see the meteoric rise of Node.js, but coming from a background of Python I really preferred a cleaner syntax.

In any fast moving community it is inevitable that things will change, and so today we see a big shift toward ES6, the new version of Javascript. It incorporates a handful of the nicer features from CoffeeScript and is usable today through tools like Babel. Here are some of my thoughts and issues on moving away from CoffeeScript in favor of ES6.

While reading I suggest keeping open a tab to Babel's learning ES6 page. The examples there are great.

Punctuation

Holy punctuation, Batman! Say goodbye to your whitespace and hello to parenthesis, curly braces, and semicolons again. Even with the advanced ES6 syntax you'll find yourself writing a lot more punctuatio

	# -- coding: utf-8 --

	import cv2
	import numpy as np
	import chainer
	import chainer.links as L
	from chainer import Chain, Variable
	from chainer import datasets

	class SOM(Chain):

	# License:
	# I hereby state this snippet is below "threshold of originality" where applicable (public domain).
	#
	# Otherwise, since initially posted on Stackoverflow, use as:
	# CC-BY-SA 3.0 skyking, Glenn Maynard, Axel Huebl
	# http://stackoverflow.com/a/31047259/2719194
	# http://stackoverflow.com/a/4858123/2719194

	import types

	WARNING: old DATASOURCENAME 'HMDB36CHEBI' doesn't match new DATASOURCENAME 'HMDB-CHEBI-WIKIDATA'
	INFO: Lm is only in new database
	INFO: Number of ids in Lm: 2565
	INFO: Number of ids in Wd (Wikidata): 21293 (3208 added, 152 removed -> overall changed +16.8%)
	INFO: Number of ids in Ck (KEGG Compound): 15941 (51 added, 6 removed -> overall changed +0.3%)
	INFO: Number of ids in Wi (Wikipedia): 4731 (745 added, 5 removed -> overall changed +18.5%)
	INFO: Number of ids in Kd (KEGG Drug): 2006 (270 added, 670 removed -> overall changed -16.6%)
	WARNING: Number of ids in Kd has shrunk by more than 10%
	INFO: Ik is only in new database
	INFO: Number of ids in Ik: 41392

	### Dockerfile
	FROM ubuntu
	RUN apt-get update && apt-get install -yq xvfb
	ADD xvfb-run-wrapper.sh /bin/xvfb-run-wrapper.sh
	RUN chmod +x /bin/xvfb-run-wrapper.sh
	ENTRYPOINT ["/bin/xvfb-run-wrapper.sh", "/bin/sleep"]
	CMD ["10000"]
	###

	### xvfb-run-wrapper.sh

	//BASIC TRAVERSAL
	// Get names for all elements in a BioPAX OWL file and then for just Proteins
	import org.biopax.paxtools.io.BioPAXIOHandler;
	import org.biopax.paxtools.io.SimpleIOHandler;
	import org.biopax.paxtools.model.Model;
	import org.biopax.paxtools.model.BioPAXElement;
	import org.biopax.paxtools.model.level3.Protein;

	// Load a sample test BioPAX File via Simple IO Handler
	InputStream f = new FileInputStream(new File("data/biopax3-short-metabolic-pathway.owl"));