operator overload

Watching this Redux Crash Course video, Brad uses
  this.setState({[e.target.name]: e.target.value});
I could guess what that was doing, but had to ask what that syntax was called - "computed keys" or "computed property names"

In terms of JS, there's definitely a drive for conciseness. Which can pay some dividends in terms of letting experienced coders recognize a complex trope quickly, but also comes with potential ambiguity - sometimes i personally wish the language was a bit more verbose, even if function() { }s are ugly,  bar fat arrows or random floating {}s can be so hard to parse.

Anyhoo, a coworker recommended this guide to ES6 features - it's pretty cool in showing the old and busted after the new hotness.

Of all the new syntaxes, one sticks out as clunky, and the other sticks out as just plain bad and confusing.

Custom Interprolation:
new hotness:
get`http://example.com/foo?bar=${bar + baz}&quux=${quux}`

is the same as 

get([ "http://example.com/foo?bar=", "&quux=", "" ],bar + baz, quux);

Dividing a string that way seems very strange.

But Parameter Context Matching seems really ugly when it starts letting you declare a local variable from a totally different argument map entry....
I mean 

function f ([ name, val ]) {

    console.log(name, val)

}

and

function h ({ name, val }) {

    console.log(name, val)

}

make sense and are pretty easy to read, but the renaming that goes on with

function g ({ name: n, val: v }) {

    console.log(n, v)

}

is bizarre - it feels like it's messing with left / right operands, every else in js land the key / variable name you're changing is on the left...

(Random note: the video made use of http://jsonplaceholder.typicode.com/ which seems pretty hip.)