RFC8785.DecodeError exception (rfc8785 v1.0.0)

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Raised by RFC8785.canonicalize!/1 and RFC8785.decode!/1 when a JSON text is invalid or unsafe to use as JCS input.

Reasons a text is rejected:

  • a syntax error or invalid byte, reported by OTP's :json parser
  • truncated input
  • data after the end of the document, other than whitespace
  • a fraction- or exponent-form number outside the IEEE-754 double range, such as 1e400
  • an unpaired surrogate in a \u escape sequence
  • a Unicode noncharacter in a string or object name
  • a duplicate object name, which RFC 8785 forbids via its I-JSON (RFC 7493) input requirement and which :json.decode/1 alone would silently drop
  • a number token that decodes to IEEE-754 negative zero, rejected following RFC 8785 erratum 7920

:reason is a stable atom, so callers can branch on the cause without parsing prose; :message explains it.

Summary

Types

reason()

Why the text was rejected

t()

Types

reason()

@type reason() ::
  :syntax
  | :unexpected_end
  | :trailing_data
  | :number_out_of_range
  | :unpaired_surrogate
  | :noncharacter
  | :duplicate_name
  | :negative_zero

Why the text was rejected:

  • :syntax — a syntax error or invalid byte
  • :unexpected_end — truncated input, or an escape cut short
  • :trailing_data — non-whitespace after the document
  • :number_out_of_range — a number literal outside the IEEE-754 double range, such as 1e400
  • :unpaired_surrogate — an unpaired surrogate in a \u escape
  • :noncharacter — a Unicode noncharacter, which I-JSON excludes
  • :duplicate_name — a duplicate object name, which I-JSON forbids
  • :negative_zero — a number token decoding to IEEE-754 negative zero, rejected per RFC 8785 erratum 7920

t()

@type t() :: %RFC8785.DecodeError{
  __exception__: term(),
  message: String.t(),
  reason: reason()
}