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// Copyright 2014 the V8 project authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
(function(global, utils) {
"use strict";
%CheckIsBootstrapping();
// -------------------------------------------------------------------
// Imports
var GlobalString = global.String;
var IteratorPrototype = utils.ImportNow("IteratorPrototype");
var iteratorSymbol = utils.ImportNow("iterator_symbol");
var MakeTypeError;
var stringIteratorIteratedStringSymbol =
utils.ImportNow("string_iterator_iterated_string_symbol");
var stringIteratorNextIndexSymbol =
utils.ImportNow("string_iterator_next_index_symbol");
var toStringTagSymbol = utils.ImportNow("to_string_tag_symbol");
utils.Import(function(from) {
MakeTypeError = from.MakeTypeError;
});
// -------------------------------------------------------------------
function StringIterator() {}
// 21.1.5.1 CreateStringIterator Abstract Operation
function CreateStringIterator(string) {
var s = TO_STRING(string);
var iterator = new StringIterator;
SET_PRIVATE(iterator, stringIteratorIteratedStringSymbol, s);
SET_PRIVATE(iterator, stringIteratorNextIndexSymbol, 0);
return iterator;
}
// ES6 section 21.1.5.2.1 %StringIteratorPrototype%.next ( )
function StringIteratorNext() {
var iterator = this;
var value = UNDEFINED;
var done = true;
if (!IS_SPEC_OBJECT(iterator) ||
!HAS_DEFINED_PRIVATE(iterator, stringIteratorNextIndexSymbol)) {
throw MakeTypeError(kIncompatibleMethodReceiver,
'String Iterator.prototype.next');
}
var s = GET_PRIVATE(iterator, stringIteratorIteratedStringSymbol);
if (!IS_UNDEFINED(s)) {
var position = GET_PRIVATE(iterator, stringIteratorNextIndexSymbol);
var length = TO_UINT32(s.length);
if (position >= length) {
SET_PRIVATE(iterator, stringIteratorIteratedStringSymbol, UNDEFINED);
} else {
var first = %_StringCharCodeAt(s, position);
value = %_StringCharFromCode(first);
done = false;
position++;
if (first >= 0xD800 && first <= 0xDBFF && position < length) {
var second = %_StringCharCodeAt(s, position);
if (second >= 0xDC00 && second <= 0xDFFF) {
value += %_StringCharFromCode(second);
position++;
}
}
SET_PRIVATE(iterator, stringIteratorNextIndexSymbol, position);
}
}
return %_CreateIterResultObject(value, done);
}
// 21.1.3.27 String.prototype [ @@iterator ]( )
function StringPrototypeIterator() {
return CreateStringIterator(this);
}
//-------------------------------------------------------------------
%FunctionSetPrototype(StringIterator, {__proto__: IteratorPrototype});
%FunctionSetInstanceClassName(StringIterator, 'String Iterator');
utils.InstallFunctions(StringIterator.prototype, DONT_ENUM, [
'next', StringIteratorNext
]);
%AddNamedProperty(StringIterator.prototype, toStringTagSymbol,
"String Iterator", READ_ONLY | DONT_ENUM);
utils.SetFunctionName(StringPrototypeIterator, iteratorSymbol);
%AddNamedProperty(GlobalString.prototype, iteratorSymbol,
StringPrototypeIterator, DONT_ENUM);
})
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