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Re: Style: new String( "abc" )

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Thomas 'PointedEars' Lahn schrieb:
> Andreas Bergmaier wrote:
>
>> Current compilers don't convert anything to an
>> object any more here, they just call the native
>> `String.prototype.charAt` method directly on the primitive value.
>
> Cite evidence.

This should get you started: 
http://stackoverflow.com/questions/17256182/what-is-the-difference-between-string-literals-and-string-objects-in-javascript
The speed tests (http://jsperf.com/heera-string-literal-vs-object) 
linked from there speak for themselves.
You can read yourself through the V8 code, they do distinguish between 
primitive values and objects a lot to gain extra optimisations.
I couldn't locate the exact code myself, but when you have to look up a 
property on a primitive value you can directly jump to the respective 
prototype intrinsic object. There's no need to create a wrapper object, 
unless the lookup turns out to become a method call of a sloppy-mode 
function.

I also found this bug 
report:http://code.google.com/p/v8/issues/detail?id=1212 which seems to 
have been forgotten in 2011.

  Bergi

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Re: Style: new String( "abc" ) Andreas Bergmaier <andber93@web.de> - 2015-06-02 21:25 +0200
  Re: Style: new String( "abc" ) Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-06-02 22:27 +0200
    Re: Style: new String( "abc" ) Andreas Bergmaier <andber93@web.de> - 2015-06-02 23:51 +0200
      Re: Style: new String( "abc" ) Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-06-03 01:17 +0200
        Re: Style: new String( "abc" ) Andreas Bergmaier <andber93@web.de> - 2015-06-03 06:22 +0200
          Re: Style: new String( "abc" ) Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-06-03 07:57 +0200
            Re: Style: new String( "abc" ) Andreas Bergmaier <andber93@web.de> - 2015-06-03 18:36 +0200
          Re: Style: new String( "abc" ) John Harris <niam@jghnorth.org.uk.invalid> - 2015-06-03 15:38 +0100

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