%TypedArray%.of does not use @@species #1157

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1. allenwb commented on Mar 29, 2018

   

   allenwb

   on Mar 29, 2018

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   No, it's correct as written and handled exactly the same as in %Array%.of

   of is a factory method of the constructor so the actual class constructor to be instantiated is the thisValue passed to the factory. What the algorithm is doing is approximately this:

   class %TypedArray% {
      of(...args) {
         let ta = new this(args.length
         for (let i=0; ++1; i<args.length) ta[i]=args[i];
         return ta;
     }
   }

   When used in an expression referencing a subclass such as Int32Array.of(1,2,3) the value of this within the inherited method will be %Int32Array%. Essentially the expression is explicitly naming the kind of typed array it wants to instantiate.

   @@species is primarily for use in instance methods that create derived collections whose class isn't explicit stated at the usage site.
2. ljharb

   closed this as completedon Apr 1, 2018
3. ljharb

   added

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   on Apr 1, 2018