32 lines
803 B
JavaScript
32 lines
803 B
JavaScript
class KatexExpressionShim extends HTMLElement {
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static observedAttributes = ["expression", "katex-options"];
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targetSpan;
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constructor() {
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super();
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}
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doRender() {
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if (!this.targetSpan) return;
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const options = this.hasAttribute("katex-options") ?
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this.getAttribute("katex-options") : {};
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katex.render(
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this.getAttribute("expression"),
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this.targetSpan,
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JSON.parse(options)
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);
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}
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connectedCallback() {
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this.targetSpan = document.createElement('span');
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this.appendChild(this.targetSpan);
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this.doRender();
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}
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attributeChangedCallback(name, oldValue, newValue) {
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this.doRender();
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}
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}
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customElements.define("katex-expression", KatexExpressionShim);
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