Function pgx::varlena::vartag_size

pub unsafe fn vartag_size(tag: vartag_external) -> usize

#define VARTAG_SIZE(tag) \
     ((tag) == VARTAG_INDIRECT ? sizeof(varatt_indirect) : \
      VARTAG_IS_EXPANDED(tag) ? sizeof(varatt_expanded) : \
      (tag) == VARTAG_ONDISK ? sizeof(varatt_external) : \
      TrapMacro(true, "unrecognized TOAST vartag"))