The util module provides essential utilities for debugging, formatting, and working with callbacks. Here's how to use it.
promisify#
callbackify#
format and formatWithOptions#
inspect#
debuglog#
types#
deprecate#
inherits (Legacy)#
getSystemErrorName#
parseArgs#
TextEncoder/TextDecoder#
Best Practices#
Promisify:
✓ Convert callback APIs
✓ Use with async/await
✓ Define custom behavior
✓ Handle multiple values
Debugging:
✓ Use debuglog for dev
✓ Use inspect for logging
✓ Add custom inspect methods
✓ Format with colors
Type Checking:
✓ Use util.types
✓ Check native types
✓ Validate inputs
✓ Handle edge cases
Avoid:
✗ Using inherits (use class)
✗ Ignoring deprecation
✗ Complex format strings
✗ Excessive inspection depth
Conclusion#
The util module provides essential utilities for Node.js development. Use promisify for callback-to-promise conversion, debuglog for conditional logging, and inspect for detailed object visualization. The types namespace offers reliable type checking, and parseArgs simplifies CLI argument parsing.