import{noChange as t}from'../lit-html.js';import{directive as s,Directive as i,PartType as r}from'../directive.js';
/**
* @license
* Copyright 2018 Google LLC
* SPDX-License-Identifier: BSD-3-Clause
*/const e=s(class extends i{constructor(t){if(super(t),t.type!==r.ATTRIBUTE||"class"!==t.name||t.strings?.length>2)throw Error("`classMap()` can only be used in the `class` attribute and must be the only part in the attribute.")}render(t){return" "+Object.keys(t).filter((s=>t[s])).join(" ")+" "}update(s,[i]){if(void 0===this.it){this.it=new Set,void 0!==s.strings&&(this.st=new Set(s.strings.join(" ").split(/\s/).filter((t=>""!==t))));for(const t in i)i[t]&&!this.st?.has(t)&&this.it.add(t);return this.render(i)}const r=s.element.classList;for(const t of this.it)t in i||(r.remove(t),this.it.delete(t));for(const t in i){const s=!!i[t];s===this.it.has(t)||this.st?.has(t)||(s?(r.add(t),this.it.add(t)):(r.remove(t),this.it.delete(t)))}return t}});export{e as classMap};
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