JSON with Duplicate Keys
A JSON object that repeats several member names (name, tags, timeout, active). RFC 8259 permits duplicate keys but leaves the result parser-defined — most keep the last. A fixture for testing how a JSON parser resolves duplicates.
{
"id": 1,
"name": "first value",
"name": "second value",
"tags": ["a"],
"tags": ["a", "b", "c"],
"config": {
"timeout": 30,
"timeout": 60,
"retries": 3
},
"active": true,
"active": false
}
Specifications
- Note
- duplicate object member names (id/name/tags/timeout/active)
- Spec
- RFC 8259 permits; behaviour is parser-defined (usually last-wins)
What is a .json file?
JSON (JavaScript Object Notation) is a lightweight, text-based data-interchange format representing objects, arrays, strings, numbers, booleans, and null. It is language-independent, human-readable, and the dominant format for web APIs and configuration. It requires a single well-formed root value.
How to use this file
Use an example JSON file to test parsers and serializers, schema validation, Unicode and number-precision handling, and API request or response processing.
Code examples
import json
with open("duplicate-keys.json") as f:
data = json.load(f)
print(type(data), len(data))Related files
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