Is that actually the case? The reference I see for 1-9 in the spec is not talking about length of the number, but is referring to digits 1,2,3...,9 as a single

Is that actually the case? The reference I see for 1-9 in the spec is not talking about length of the number, but is referring to digits 1,2,3...,9 as a single token in the grammar. digit1-9 is a token that's used to disallow leading zeros: a number must start (ignoring the possibility of "-" prefix) with a `digit1-9` which may then be followed by any number of `digit` tokens (inclusive of the digit "0" this time), or else it must start with a "0" which may only be followed by "." etc. I don't see any reference to range/precision in the spec, other than the suggestion that numbers that can be represented as an IEEE double are likely to be interoperable, and integers within 53 bits of range will generally be interoperable due to exact agreement on their value.