Result!(typeof(this), DecimalParseError). Failures:
EMPTY, MALFORMED (offset), PRECISION (significant digits > P), EXPONENT (outside the biased range), PAYLOAD.
Exact parse. Grammar: [+-]? digits [ '.' digits ] [ (e|E)
[+-]? digits ], or Inf, Infinity, NaN[ddddd], sNaN[ddddd] (with optional sign on NaN per IEEE 754-2019).
Result!(typeof(this), DecimalParseError). Failures:
EMPTY, MALFORMED (offset), PRECISION (significant digits > P), EXPONENT (outside the biased range), PAYLOAD.