Merge branch 'main' into transcend

Author: michaelficarra

README.md

@@ -296,10 +296,9 @@ function* naturals() {
 naturals().find(v => v > 1); // 2
 ```
 
-### `.from(object)`
+### `Iterator.from(object)`
 
-`.from` takes an object as an argument. This method allows wrapping "iterator-like" objects with an
-iterator.
+`.from` is a _static_ method (unlike the others listed above) which takes an object as an argument. This method allows wrapping "iterator-like" objects with an iterator.
 
 Returns the object if it is already an iterator, returns a wrapping iterator if the passed object
 implements a callable @@iterator property.

spec.html

@@ -129,12 +129,14 @@ <h1>
       <h1>
         GetIteratorFlattenable (
           _obj_: an ECMAScript language value,
+          _stringHandling_: ~iterate-strings~ or ~reject-strings~,
         ): either a normal completion containing an Iterator Record or a throw completion
       </h1>
       <dl class="header">
       </dl>
       <emu-alg>
-        1. If _obj_ is not an Object, throw a *TypeError* exception.
+        1. If _obj_ is not an Object, then
+          1. If _stringHandling_ is ~reject-strings~ or _obj_ is not a String, throw a *TypeError* exception.
         1. Let _method_ be ? GetMethod(_obj_, @@iterator).
         1. If _method_ is *undefined*, then
           1. Let _iterator_ be _obj_.
@@ -187,8 +189,7 @@ <h1>Iterator.prototype</h1>
         <emu-clause id="sec-iterator.from">
           <h1>Iterator.from ( _O_ )</h1>
           <emu-alg>
-            1. If _O_ is a String, set _O_ to ! ToObject(_O_).
-            1. Let _iteratorRecord_ be ? GetIteratorFlattenable(_O_).
+            1. Let _iteratorRecord_ be ? GetIteratorFlattenable(_O_, ~iterate-strings~).
             1. Let _hasInstance_ be ? OrdinaryHasInstance(%Iterator%, _iteratorRecord_.[[Iterator]]).
             1. If _hasInstance_ is *true*, then
               1. Return _iteratorRecord_.[[Iterator]].
@@ -443,7 +444,7 @@ <h1>Iterator.prototype.flatMap ( _mapper_ )</h1>
               1. Let _value_ be ? IteratorValue(_next_).
               1. Let _mapped_ be Completion(Call(_mapper_, *undefined*, « _value_, 𝔽(_counter_) »)).
               1. IfAbruptCloseIterator(_mapped_, _iterated_).
-              1. Let _innerIterator_ be Completion(GetIteratorFlattenable(_mapped_)).
+              1. Let _innerIterator_ be Completion(GetIteratorFlattenable(_mapped_, ~reject-strings~)).
               1. IfAbruptCloseIterator(_innerIterator_, _iterated_).
               1. Let _innerAlive_ be *true*.
               1. Repeat, while _innerAlive_ is *true*,