yippee.fun
Precise DOM morphing
morphing
typescript
dom
Use `moveBefore`
joel.drapper.me
+9
-1
src/morphlex.ts
+9
-1
src/morphlex.ts
···
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73
else throw new Error("[Morphlex] The string was not a valid HTML node.")
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}
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+
// Feature detection for moveBefore support (cached for performance)
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const supportsMoveBefore = typeof Element.prototype.moveBefore === "function"
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+
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class Morph {
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readonly #idMap: IdMap
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···
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#insertBefore(parent: ParentNode, node: Node, insertionPoint: ChildNode): void {
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if (node === insertionPoint) return
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-
parent.insertBefore(node, insertionPoint)
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+
// Use moveBefore when available (more efficient for moving existing nodes)
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if (supportsMoveBefore) {
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;(parent as any).moveBefore(node, insertionPoint)
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} else {
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parent.insertBefore(node, insertionPoint)
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}
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}
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#appendChild(node: ParentNode, newNode: Node): void {