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// Copyright 2019 Google, Inc. All rights reserved.
// This code is governed by the BSD license found in the LICENSE file.
/*---
esid: prod-OptionalExpression
description: >
demonstrate syntax-based short-circuiting.
info: |
If the expression on the LHS of ?. evaluates to null/undefined, the RHS is
not evaluated
features: [optional-chaining]
---*/
const a = undefined;
let x = 1;
a?.[++x] // short-circuiting.
a?.b.c(++x).d; // long short-circuiting.
undefined?.[++x] // short-circuiting.
undefined?.b.c(++x).d; // long short-circuiting.
assert.sameValue(1, x);
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