JSON Object Duplicate Key Span Pair Tool

Description

Compare leftKey and rightKey literally and return their offsets only when equal.

A JSON member can be absent, present with null, or present with an empty string. Testing own-property presence preserves those distinctions instead of relying on truthiness.

Compare leftKey and rightKey literally and return their offsets only when equal.

When to use this tool

Use JSON Object Duplicate Key Span Pair when you need an explicit object-member presence or key comparison.

How to use the tool and how it works

Enter leftKey, leftOffset, rightKey, rightOffset. Use the units and conventions below.
Run the tool. Correct any format, range, or cross-field input error before interpreting the output.
Read duplicate, offsets. Inspect duplicate before interpreting the associated values.

Require ordered nonnegative offsets with leftOffset < rightOffset. Compare leftKey and rightKey literally and return their offsets only when equal.^[1]

Input field	Meaning and units	Accepted input
leftKey	Left Key	Required. Text; maximum UTF-16 length 8192.
leftOffset	Left Offset	Required. Safe integer; minimum 0.
rightKey	Right Key	Required. Text; maximum UTF-16 length 8192.
rightOffset	Right Offset	Required. Safe integer; minimum 0.

Output field	Interpretation	Returned shape
duplicate	Duplicate	Required. Boolean.
offsets	Offsets	Required. Array of safe integer; maximum items 256.

json

{
  "input": {
    "leftKey": "a",
    "leftOffset": 1,
    "rightKey": "a",
    "rightOffset": 8
  },
  "output": {
    "duplicate": true,
    "offsets": [
      1,
      8
    ]
  }
}

Limitations and assumptions

This inspects a supplied pair rather than scanning JSON; escape-equivalent keys must already be decoded if they should compare equal.
Inputs must satisfy both the field types and the cross-field conditions above. Invalid input causes an error; a successful false flag or documented placeholder is a different result.
Numeric calculations use binary floating point unless exact decimal-integer arithmetic is explicitly stated. No hidden measurement tolerance or decimal rounding is added; nonfinite or out-of-contract results are rejected. Numeric signed-zero results are exported as zero.

Alternative or Complementary methods

Use a complete schema and document comparison when conditional requirements or nested structures matter.

References

Calculation and input contract: json/json-object-duplicate-key-span-pair — tool.io

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