String is open and dynamic!

P T Withington ptw at
Thu Sep 27 16:38:09 PDT 2007

Oh right.  I hate primitive types.  Everywhere in my code I have to say:

   typeof x == 'string'  || x instanceof String

Will this get any better in es4?  I seem to recall that Dylan somehow  
kept Number open but sealed Integer and Float so you could have  
competitive numeric performance and still permit a user throwing in a  
Complex library.  Couldn't string be a sealed subclass of String so I  
can be generic if I use String, or I can restrict myself to string  
and be fast?

On 2007-09-27, at 09:58 EDT, Lars T Hansen wrote:

> You can subclass "String" but not "string", and the latter is not a
> subclass of the former, which is just a container class.  So I might
> not open the Champagne quite yet, if I were you.
> --lars
> On 9/27/07, P T Withington <ptw at> wrote:
>> I was just about to ask if I would be able to subclass String in es4,
>> and I find I can!  Hurray!
>> (Because the OpenLaszlo debugger creates 'annotated' strings with its
>> printf method that remember the objects associated with each string
>> representation.  I have to kludge this in es3 because these annotated
>> strings are not instances of String...)
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