53 lines
2.2 KiB
JavaScript
53 lines
2.2 KiB
JavaScript
// https://github.com/alangpierce/sucrase/tree/265887868966917f3b924ce38dfad01fbab1329f
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//
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// The MIT License (MIT)
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//
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// Copyright (c) 2012-2018 various contributors (see AUTHORS)
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//
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// Permission is hereby granted, free of charge, to any person obtaining a copy
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// of this software and associated documentation files (the "Software"), to deal
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// in the Software without restriction, including without limitation the rights
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// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
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// copies of the Software, and to permit persons to whom the Software is
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// furnished to do so, subject to the following conditions:
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//
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// The above copyright notice and this permission notice shall be included in all
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// copies or substantial portions of the Software.
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//
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// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
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// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
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// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
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// SOFTWARE.
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/**
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* Polyfill for the nullish coalescing operator (`??`).
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*
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* Note that the RHS is wrapped in a function so that if it's a computed value, that evaluation won't happen unless the
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* LHS evaluates to a nullish value, to mimic the operator's short-circuiting behavior.
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*
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* Adapted from Sucrase (https://github.com/alangpierce/sucrase)
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*
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* @param lhs The value of the expression to the left of the `??`
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* @param rhsFn A function returning the value of the expression to the right of the `??`
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* @returns The LHS value, unless it's `null` or `undefined`, in which case, the RHS value
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*/
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function _nullishCoalesce(lhs, rhsFn) {
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// by checking for loose equality to `null`, we catch both `null` and `undefined`
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return lhs != null ? lhs : rhsFn();
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}
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// Sucrase version:
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// function _nullishCoalesce(lhs, rhsFn) {
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// if (lhs != null) {
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// return lhs;
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// } else {
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// return rhsFn();
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// }
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// }
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export { _nullishCoalesce };
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//# sourceMappingURL=_nullishCoalesce.js.map
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