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How would you stream-parse a very large JSON file without loading it entirely into memory?

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Answer

Standard JSON.parse() requires the full string in memory first. For huge files, use a streaming JSON parser (like a library built on Node's Readable streams or the browser's ReadableStream) that emits parsed tokens or objects incrementally as chunks of the file arrive.
// Conceptual: streaming parser emits events per JSON value
const parser = createStreamingJsonParser();
parser.on('value', (item) => processItem(item));
fs.createReadStream('huge.json').pipe(parser);
Real-world example Processing a multi-gigabyte JSON export file on a server without running out of memory.

Common follow-ups: What's a JSON Lines (.jsonl) format, and how does it make streaming parsing simpler?

Async Iterators & Streams
All 10 JSON & Data Serialization questions