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node_modules/core-js/modules/esnext.iterator.flat-map.js

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+'use strict';
+var $ = require('../internals/export');
+var call = require('../internals/function-call');
+var aCallable = require('../internals/a-callable');
+var anObject = require('../internals/an-object');
+var getIteratorDirect = require('../internals/get-iterator-direct');
+var getIteratorFlattenable = require('../internals/get-iterator-flattenable');
+var createIteratorProxy = require('../internals/iterator-create-proxy');
+var iteratorClose = require('../internals/iterator-close');
+var IS_PURE = require('../internals/is-pure');
+
+var IteratorProxy = createIteratorProxy(function () {
+  var iterator = this.iterator;
+  var mapper = this.mapper;
+  var result, inner;
+
+  while (true) {
+    if (inner = this.inner) try {
+      result = anObject(call(inner.next, inner.iterator));
+      if (!result.done) return result.value;
+      this.inner = null;
+    } catch (error) { iteratorClose(iterator, 'throw', error); }
+
+    result = anObject(call(this.next, iterator));
+
+    if (this.done = !!result.done) return;
+
+    try {
+      this.inner = getIteratorFlattenable(mapper(result.value, this.counter++), false);
+    } catch (error) { iteratorClose(iterator, 'throw', error); }
+  }
+});
+
+// `Iterator.prototype.flatMap` method
+// https://github.com/tc39/proposal-iterator-helpers
+$({ target: 'Iterator', proto: true, real: true, forced: IS_PURE }, {
+  flatMap: function flatMap(mapper) {
+    anObject(this);
+    aCallable(mapper);
+    return new IteratorProxy(getIteratorDirect(this), {
+      mapper: mapper,
+      inner: null
+    });
+  }
+});