Function set_body_pointer 

pub fn set_body_pointer(
    body: &mut Value,
    pointer: &str,
    value: Value,
) -> Result<(), FaucetError>

Write value into body at the RFC 6901 JSON Pointer pointer (#748).

The pointer must address an existing scalar (or null) — or a missing final key whose parent is an existing object. Intermediate objects and array elements are never created, and an object/array target is refused (a bind replaces a value; it does not merge).