; Transaction-header metadata is visible to posting-level `tag()` lookups.
; Here, the `Statement: foobar` is declared on the transaction header but
; the tag block validates it via the `tag()` value binding.
tag Statement
    assert value =~ /^foo/

2024-01-01 Test
    ; Statement: foobar
    Expenses:Food  $10.00
    Assets:Checking
