 --> [ local path prefix ]/structs/format_too_many_repls.fpp:1:30
  |
1 | struct s { x: U32 format "{} {} {}" }
  |                              ^^ extraneous format replacement field
  |
 ::: [ local path prefix ]/structs/format_too_many_repls.fpp:1:33
  |
1 | struct s { x: U32 format "{} {} {}" }
  |                                 ^^ extraneous format replacement field

