core-js
Version:
Standard library
35 lines (32 loc) • 1.34 kB
JavaScript
;
var createIteratorConstructor = require('../internals/create-iterator-constructor');
var requireObjectCoercible = require('../internals/require-object-coercible');
var InternalStateModule = require('../internals/internal-state');
var codePointAt = require('../internals/string-at');
var STRING_ITERATOR = 'String Iterator';
var setInternalState = InternalStateModule.set;
var getInternalState = InternalStateModule.getterFor(STRING_ITERATOR);
// TODO: unify with String#@@iterator
var $StringIterator = createIteratorConstructor(function StringIterator(string) {
setInternalState(this, {
type: STRING_ITERATOR,
string: string,
index: 0
});
}, 'String', function next() {
var state = getInternalState(this);
var string = state.string;
var index = state.index;
var point;
if (index >= string.length) return { value: undefined, done: true };
point = codePointAt(string, index, true);
state.index += point.length;
return { value: { codePoint: codePointAt(point, 0), position: index }, done: false };
});
// `String.prototype.codePoints` method
// https://github.com/tc39/proposal-string-prototype-codepoints
require('../internals/export')({ target: 'String', proto: true }, {
codePoints: function codePoints() {
return new $StringIterator(String(requireObjectCoercible(this)));
}
});