Free · List every repeating code block

JavaScript Loop Inventory

Find for, for-of, for-in, while, and do-while loops with lines and nesting.

Real Acorn 8.18 parser
Private in your browser
Code is parsed, never run

List JavaScript loops

Paste JavaScript, choose module or script mode, and let Acorn inspect the syntax without running the code.

Add JavaScriptThe code is parsed, never run

JavaScript source 1,028 / 120,000 characters

import { formatPrice } from "./money.js";
export const storeName = "Little Leaf Market";

const products = [
  { id: 1, name: "Garden Tote", price: 3499, tags: ["gift", "summer"] },
  { id: 2, name: "Seed Pack", price: 999, tags: ["garden"] },
];

class Cart {
  constructor(items = []) {
    this.items = items;
  }

async total() {
    const prices = await Promise.resolve(this.items.map((item) => item.price));
    return prices.reduce((sum, price) => sum + price, 0);
  }
}

export async function showProducts(customer) {
  // Keep only products this customer can see.
  const visible = products.filter((product) => product.price > 0);
  for (const product of visible) {
    console.log(product.name, formatPrice(product.price));
  }

document.querySelector("#buy")?.addEventListener("click", () => {
    console.log(customer?.name ?? "Guest");
  });

if (visible.length === 0) return "No products";
  return visible.map(({ name }) => name).join(", ");
}

export const loadDetails = async () => import("./details.js");

Private syntax parsingAcorn 8.18.0 · latest ECMAScript · code is never executed

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Acorn can check syntax and find code parts without running a single line.

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How to use it

Paste JavaScript or open a file.
Run the local Acorn parser.
Review or download the clear result.

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Acorn reads the JavaScript inside this browser tab and never runs it. Bookify does not upload or save the code. Input, syntax-tree depth, node count, table rows, and AST JSON all have clear limits.