41 lines
1.1 KiB
JavaScript
41 lines
1.1 KiB
JavaScript
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/**
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* @license
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* Copyright 2021 Google LLC
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* SPDX-License-Identifier: BSD-3-Clause
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*/
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/**
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* Chooses and evaluates a template function from a list based on matching
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* the given `value` to a case.
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*
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* Cases are structured as `[caseValue, func]`. `value` is matched to
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* `caseValue` by strict equality. The first match is selected. Case values
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* can be of any type including primitives, objects, and symbols.
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*
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* This is similar to a switch statement, but as an expression and without
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* fallthrough.
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*
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* @example
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*
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* ```ts
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* render() {
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* return html`
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* ${choose(this.section, [
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* ['home', () => html`<h1>Home</h1>`],
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* ['about', () => html`<h1>About</h1>`]
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* ],
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* () => html`<h1>Error</h1>`)}
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* `;
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* }
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* ```
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*/
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export const choose = (value, cases, defaultCase) => {
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for (const c of cases) {
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const caseValue = c[0];
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if (caseValue === value) {
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const fn = c[1];
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return fn();
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}
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}
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return defaultCase === null || defaultCase === void 0 ? void 0 : defaultCase();
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};
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//# sourceMappingURL=choose.js.map
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