RFC 8259, "The JavaScript Object Notation (JSON) Data Interchange Format", December 2017

Errata ID: 7600
Status: Reported
Type: Technical
Publication Format(s) : TEXT
Reported By: Guillaume Fortin-Debigaré
Date Reported: 2023-08-11

Section 6 says:

   The representation of numbers is similar to that used in most
   programming languages.  A number is represented in base 10 using
   decimal digits.  It contains an integer component that may be
   prefixed with an optional minus sign, which may be followed by a
   fraction part and/or an exponent part.  Leading zeros are not
   allowed.

It should say:

   The representation of numbers is similar to that used in most
   programming languages.  A number is represented in base 10 using
   decimal digits.  It contains an integer component that may be
   prefixed with an optional minus sign, which may be followed by a
   fraction part and/or an exponent part.  Leading zeros in the
   integer component beyond the units digit are not allowed.

Notes:

The original wording about leading zeros contradicts the documented ABNF grammar for JSON numbers in the following cases:
- If the integer component is equal to 0 and the fractional component exists. (Examples: 0.1, 0.001)
- In the exponent part, after the letter E or e or the optional sign. (Example: 1E01)

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