Normative: Add Exponentiation Operator

[rwaldron]

No description provided.

[michaelficarra]

I know I'm bikeshedding here, but calling this production IncrementExpression really bothers me when two of the four possibilities is a decrement. The SpiderMonkey AST called this an UpdateExpression. Could we go with that instead?

[rwaldron]

Yes, I like that better. Update to follow

[anba]

I still think we should use the default operator evaluation order for the exponentiation operator (tc39/proposal-exponentiation-operator#10). The current implementations in Edge and SpiderMonkey also use the default evaluation order.

var leftValue = {valueOf(){ print("left-value"); return 3; }};
var rightValue = {valueOf(){ print("right-value"); return 2; }};

// Output with current proposal:  "left", "leftValue", "right", "rightValue"
// Default operator evaluation order: "left", "right", "leftValue", "rightValue"
print((print("left"), leftValue )**(print("right"), rightValue));

[bterlson]

@anba that is very good point. @rwaldron, thoughts? Seems confusing to have different evaluation order. Seems like what @anba suggests is in line with every other operator...

[rwaldron]

I can't really follow those notes in that issue because I don't think they're aligned with the latest version of the feature spec—I tried to matching things up, but I'm exhausted at the moment and that was a bad idea.

[rwaldron]

I see the order of ops now, that may have been me being overzealous in my "clean ups" and just overlooking the change in semantics. Thanks @anba

[rwaldron]

@anba @bterlson updated!

[bterlson]

Yessir, looks good!

[anba]

👍

[rwaldron]

@anba thanks again for taking a look at this, your attention is always greatly appreciated :)

[rwaldron]

Rebased on dfeaa39

[bterlson]

🎆

[ljharb]

🎆 ** 🎆

[rwaldron]

Thanks everyone!
On Fri, Feb 5, 2016 at 7:08 PM Jordan Harband notifications@github.com
wrote:

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