Implement the scenario utility: DOM select elements custom selector. Discuss edge cases, runtime performance, and alternative paradigms.
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Example usage
function customSelect(node, selector) {
if (!node || typeof selector !== 'string') return [];
const result = [];
// BFS queue traversal to inspect nodes iteratively and avoid stack limits
const queue = [node];
while (queue.length > 0) {
const curr = queue.shift();
if (curr.nodeType === 1) { // ELEMENT_NODE
if (typeof curr.matches === 'function' && curr.matches(selector)) {
result.push(curr);
}
}
const children = curr.children || [];
for (let i = 0; i < children.length; i++) {
queue.push(children[i]);
}
}
return result;
}
// Example placeholder (requires DOM environment)
// console.log(customSelect(document.body, 'div.card'));05
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