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Errors & debugging

Handle failures gracefully, raise helpful errors, and debug with confidence.

1 match
Errors & debugging easy

How to Validate JSON in Python and Catch JSONDecodeError

A robust Python function that attempts to parse JSON strings and returns a boolean plus either the parsed data or a descriptive error message when decoding fails.

json validation jsondecodeerror
Python 
import json

def validate_json(json_string):
    """Try to parse JSON, return (is_valid, data_or_error)."""
    try:
        data = json.loads(json_string)
        return True, data
    except json.JSONDecodeError as e:
        return False, f"Invalid JSON: {e}"

if __name__ == "__main__":
    test_inputs = [
        …
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