BSN_ERROR_LENGTH
The errorCode validateBsn returns when the input was not
exactly nine digits.
import { BSN_ERROR_LENGTH, validateBsn } from '@conduction/nextcloud-vue'
validateBsn('12345678').errorCode // BSN_ERROR_LENGTH — too short
validateBsn('12345678a').errorCode // BSN_ERROR_LENGTH — not all digits
Value: 'length'.
Distinguished from BSN_ERROR_CHECKSUM so a form can
say "a BSN is nine digits" while the user is still typing, and only complain
about the checksum once the length is right. Reporting a checksum failure on a
half-typed number is noise.
When this code is returned, elevenTestScore is -1 — the elfproef was never
computed.