20 lines
509 B
JavaScript
20 lines
509 B
JavaScript
import React, { useEffect, useState } from 'react';
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export const Heading = ({ level, observer }) => (props) => {
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useEffect(() => {
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/* start observing heading's intersection with the bounding box
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* set by observer's `rootMargin` */
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if (!observer) {
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return
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}
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const heading = document.getElementById(props.id)
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if (heading) observer.observe(heading);
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});
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return React.createElement(`h${level}`, {
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...props,
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className: "c-heading scroll-mt-16 cursor-pointer"
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})
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}
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