Subject: [CODE4LIB] help on displaying lcsh from MARC

From: Jonathan Rochkind <[email-masked]>
Date: Wed, 23 Sep 2009 10:09:50 -0400

Hi all, I'm writing some marc record display code, and I have a question 
about the 'right' way to display LCSH headings.

LCSH headings are typically displayed with "--" between components. But 
looking at the MARC, it looks like the "--" punctuation isn't actually 
in the MARC field. (A rare instance where display punctuation isn't in 
the marc!).

Is it correct for any LCSH 6xx field (which you know because the 2nd 
indicator is 0, right?), to add "--" between ALL present subfields on 
display?   Do I have the right logic there?

Thanks for any advice!

Jonathan

---

From: Tod Olson <[email-masked]>
Date: Wed, 23 Sep 2009 09:15:01 -0500

Only for certain subfields:

Dash (-) that precedes a subdivision in an extended 600 subject  
heading is not carried in the MARC record. It may be system generated  
as a display constant associated with the content of subfield $v, $x,  
$y, and $z.

 From http://www.loc.gov/marc/bibliographic/bd600.html

-Tod

On Sep 23, 2009, at 9:09 AM, Jonathan Rochkind wrote:

> Hi all, I'm writing some marc record display code, and I have a  
> question about the 'right' way to display LCSH headings.
>
> LCSH headings are typically displayed with "--" between components.  
> But looking at the MARC, it looks like the "--" punctuation isn't  
> actually in the MARC field. (A rare instance where display  
> punctuation isn't in the marc!).
>
> indicator is 0, right?), to add "--" between ALL present subfields  
> on display?   Do I have the right logic there?
>
> Thanks for any advice!
>
> Jonathan

---

From: Jonathan Rochkind <[email-masked]>
Date: Wed, 23 Sep 2009 10:19:32 -0400

Thanks!  So $v, $x, $y, and $z should always get a "--" before them -- 
that's sufficient logic to do it 'right'?  I guess an LCSH 6xx always 
needs an $a first, so I don't need to worry about if a $v or $x happens 
to come first, and shouldn't get a preceding "--".

Should I do this only for 6xx with 2nd indicator 2 indicating LCSH, or 
do people generally just do this for all 6xx?

---

From: Jonathan Rochkind <[email-masked]>
Date: Wed, 23 Sep 2009 10:20:54 -0400

Hey, and it occurs to me, in an HTML display, it might be better to use 
an actual em-dash than the traditional two hyphens too?  Since the LC 
documentation just talks about "dash" -- two hyphens is how you 
approximate an em-dash in ascii of course, but we're not living in ascii 
anymore!

---

From: Keith Jenkins <[email-masked]>
Date: Wed, 23 Sep 2009 10:37:35 -0400

Using "--" before subfields $v, $x, $y, and $z should work well for
all the standard MARC 6XX fields.

The only exception might be in any locally-defined fields 690-699.

Keith

On Wed, Sep 23, 2009 at 10:19 AM, Jonathan Rochkind <[email-masked]> wrote:
> that's sufficient logic to do it 'right'?  I guess an LCSH 6xx always needs
> an $a first, so I don't need to worry about if a $v or $x happens to come
> first, and shouldn't get a preceding "--".
>
> Should I do this only for 6xx with 2nd indicator 2 indicating LCSH, or do
> people generally just do this for all 6xx?
>
> Tod Olson wrote:
>>
>> Dash (-) that precedes a subdivision in an extended 600 subject  heading
>> is not carried in the MARC record. It may be system generated  as a display
>> constant associated with the content of subfield $v, $x,  $y, and $z.
>>
>>> looking at the MARC, it looks like the "--" punctuation isn't  actually in
>>> the MARC field. (A rare instance where display  punctuation isn't in the
>>> marc!).
>>>

---

From: Tod Olson <[email-masked]>
Date: Wed, 23 Sep 2009 09:47:44 -0500

On Sep 23, 2009, at 9:19 AM, Jonathan Rochkind wrote:

> Thanks!  So $v, $x, $y, and $z should always get a "--" before them  
> -- that's sufficient logic to do it 'right'?  I guess an LCSH 6xx  
> always needs an $a first, so I don't need to worry about if a $v or  
> $x happens to come first, and shouldn't get a preceding "--".
>
> Should I do this only for 6xx with 2nd indicator 2 indicating LCSH,  
> or do people generally just do this for all 6xx?

Our ancient hardcopy MARC 21 manual says the dash preceding any of  
those subfields is a display constant, and there is no mention of  
indicator-based display logic.  So no need to worry about the  
indicators.

I suspect this is ISBD punctuation.  If so, it's probably the only  
ISBD punctuation that is, sensibly, not carried in the data.

On Sep 23, 2009, at 9:20 AM, Jonathan Rochkind wrote:

> Hey, and it occurs to me, in an HTML display, it might be better to  
> use an actual em-dash than the traditional two hyphens too?  Since  
> the LC documentation just talks about "dash" -- two hyphens is how  
> you approximate an em-dash in ascii of course, but we're not living  
> in ascii anymore!

In fact, the old MARC 21 Format for Bibliographic Data print manual  
uses the em-dash.  I would agree that the "--" is legacy, probably  
from the days of printing cards on impact printers with the old  
Library of Congress print train.

If you go for the em-dash, it will be interesting to see how long it  
takes for someone complain about the change from the double dashes.

-Tod

>> heading is not carried in the MARC record. It may be system  
>> generated  as a display constant associated with the content of  
>> subfield $v, $x,  $y, and $z.
>>
>>> LCSH headings are typically displayed with "--" between  
>>> components.  But looking at the MARC, it looks like the "--"  
>>> punctuation isn't  actually in the MARC field. (A rare instance  
>>> where display  punctuation isn't in the marc!).
>>>
>>> Is it correct for any LCSH 6xx field (which you know because the  
>>> 2nd  indicator is 0, right?), to add "--" between ALL present  
>>> subfields  on display?   Do I have the right logic there?
>>>
>>> Thanks for any advice!
>>>
>>> Jonathan
>>>
>>
>>