Why using Local::New together with String::New()

Question

I used this:

 Local<Value> argv[argc] = { String::New("hello world") };

But now I see the example on node.js website:

 Local<Value> argv[argc] = { Local<Value>::New(String::New("hello world")) };

What does it mean? What's difference, when an dwhy I should use Local<Value> in addition to String::New()

@Joe, I have simpler functions and those that call callbacks — exebook, Mar 01 '14 at 13:49
The only code I've seen in the node addon docs use that construct in the context of a native addon calling a JS callback. But I wish I knew if it "mattered". — Joe, Mar 01 '14 at 13:56
What's particularly interesting is that the "unstable" ver (0.11.x) docs have changed to not do this... e.g. http://nodejs.org/dist/v0.11.11/docs/api/addons.html#addons_callbacks — Joe, Mar 01 '14 at 14:15

score 3 · Accepted Answer · answered Mar 01 '14 at 16:15

Apparently, the node.js example in this case was wrong/inefficient.

https://github.com/joyent/node/commit/98aad77f466d9c36947f2cbb6d07b75009795ed2#commitcomment-5532648

jnardone added a note 2 hours ago

Was this just one of those things that was always wrong, or was there an underlying v8 change that meant that this should change? The additional Local::New always looked odd but I can't tell if something buried inside v8 required this additional wrapper or not.

bnoordhuis added a note 7 minutes ago

It's cleanup. Creating a Local out of a Local is not actively harmful but it's superfluous and slightly inefficient.

So, your first format is fine.

Why using Local::New together with String::New()

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