`$string()` does not preserve full precision for large numeric values (≥ 15–16 digits)

[MaxPlamadeala-RecoLabs]

We've been having an issue with jsonata parsing of large numbers. We had this initial json (obfuscated):

"data": [
      {
        ...
        "userId": 5890840712243077,
        "createdAt": "2025-10-30T13:02:59Z",
        "modifiedAt": "2025-10-30T13:02:59Z",
      }
]

And this Jsonata expression:

$string(data[0].userId)

What it gives us is "5890840712243080" which is incorrect as you see. If I try however a smaller number like 589084071224307 (-1 digit) it works perfectly. If I try a larger nr like 589084071224307838838 it goes crazy:

As I see in src/functions.js you have this line, which cuts every number to 15 digits. Is it on purpose? Can this be fixed or do you have an analogy to propose for larger numbers?

[iovanom]

I have created a fix in this PR #762

[Turings98apprentice]

As I mentioned in PR #762 I think your bigger issue here is that you're using integers for user IDs instead of strings. Is there a functional requirement that the user IDs have to be integers? Do you have any control over that input JSON?

[iovanom]

As I mentioned in PR #762 I think your bigger issue here is that you're using integers for user IDs instead of strings. Is there a functional requirement that the user IDs have to be integers? Do you have any control over that input JSON?

The json we get from external API that we can't control. We can't change external API to get the string as id.

[andrew-coleman]

Resolved by #762