The documentation says that after a discussion (which I have not been able to find any trace of) on this list it seemed most people wanted to add a new field to the end of the hundred group it belongs to!
This sounds very peculiar to me.
If I want to add a new 001, for instance, I certainly want it to go first among the tags.
Not after a 099 field.
I think the documentation would be clearer if it said that after the discussion most people wanted the ability to add a new field to the end of the hundred group where it belonged. The reason is that according to the MARC format, fields within a record are supposed to be grouped by block (hundred groups). That means that fields may not necessarily be in tag order.
It's true a 001 will probably always appear before a 099, but in the 6XX block at least, the sequence of fields can be significant. (A 651 field may appear before a 650 field, for instance, because the subject in the 651 is more important than the subject in the 650.) You may very well want to add a field to the end of this block to ensure the subject in that field has less significance than the preceding fields, even if the field has a lower tag value. Certainly you don't need the insert_grouped_field method, but having a method to do that work for you is a real convenience that simplifies your application code.
On the issue of alpha and numeric tags, I know that alpha values in tags have been permitted in the MARC standard for a long time, and applaud the fact that MARC::Record allows for it, but has anyone actually seen one used? In some later revision of UNIMARC or one of the national standards based on UNIMARC perhaps? I'd be curious to know about specific cases people have seen.
Ron
Ron Davies Information and documentation systems consultant Av. Baden-Powell 1 Bte 2, 1200 Brussels, Belgium Email: [EMAIL PROTECTED] Tel: +32 (0)2 770 33 51 GSM: +32 (0)484 502 393
