javascript / expert
Snippet
Recursive Error Chaining with the 'cause' Property
The 'cause' property in the Error constructor allows for structured error wrapping. This preserves the original error context while providing a high-level message, which is essential for debugging complex service architectures in Node.js.
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async function fetchData() {try {await db.query('SELECT...');} catch (dbErr) {throw new Error('Failed to retrieve user data', { cause: dbErr });}}try {await fetchData();} catch (err) {console.error(err.message);console.error('Original source:', err.cause.message);}
nodejs
Breakdown
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{ cause: dbErr }
Passes the original error as metadata to the new Error instance.
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err.cause
Accesses the nested error object for deep diagnostic analysis.