# disambiguate-add-date option?

**URL:** <https://discourse.citationstyles.org/t/disambiguate-add-date-option/496>\
**Category:** CSL Development\
**Created:** [July 30, 2008, 2:53pm UTC](https://discourse.citationstyles.org/t/disambiguate-add-date-option/496 "2008-07-30T14:53:46Z")\
**Posts on this page:** 12\
**Page:** 2

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**Author:** ![Andrea\_Rossato1](https://avatars.discourse-cdn.com/v4/letter/a/e47774/32.png) [@Andrea\_Rossato1](https://discourse.citationstyles.org/u/Andrea_Rossato1)\
**Post date:** [August 4, 2008, 11:27am UTC](https://discourse.citationstyles.org/t/disambiguate-add-date-option/496/21 "2008-08-04T11:27:50Z")

</div>

> I don’t think you’re comparing the output, I think you’re comparing  
> the original data. Then there is less ambiguity, right? I agree that  
> maximum number of authors can’t be determined, but couldn’t you just  
> run a loop to find out how many there are?

the problem is that you don’t know which part of the original data  
will be used by that specific style. You may be keeping track of it by  
consuming the input, as Stephen suggested, though (which I think is  
going to make the code quite complex. But I might be wrong).

> You can look here to see how Simon does it in Zotero:  
> [https://www.zotero.org/trac/browser/extension/branches/1.0/chrome/content/zotero/xpcom/cite.js](https://www.zotero.org/trac/browser/extension/branches/1.0/chrome/content/zotero/xpcom/cite.js)
> 
> It’s true that your example styles don’t work in Zotero, but I suspect  
> they could be fixed to work–I just don’t have time to play with them  
> right now–maybe during the week.

As I said I discovered the issues my examples point out by reading the  
source code you are linking to. Maybe you are right and you can fix  
the problems easily.

What I wanted to stress is that you cannot assume, as the code does,  
that since a citation has a date field set, and the style is using the  
disambiguate-add-year-suffix option then the citation is disambiguated  
by applying this rule. It may be the case that the style is not  
actually using the date for that specific reference type, as it is the  
case with my 3rd style example.

Andrea

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**Author:** ![Andrea\_Rossato1](https://avatars.discourse-cdn.com/v4/letter/a/e47774/32.png) [@Andrea\_Rossato1](https://discourse.citationstyles.org/u/Andrea_Rossato1)\
**Post date:** [August 4, 2008, 11:41am UTC](https://discourse.citationstyles.org/t/disambiguate-add-date-option/496/22 "2008-08-04T11:41:16Z")

</div>

> My point was that the number is low and only grows with the number of  
> authors of a work, which always is a low number. So I don’t see a reason  
> to worry about performance here.

why not? the problem is not just the number of authors, but the  
complexity of the style too. You need to re-evaluate the style to  
re-generate the citation. Is the union of the complexity of the style  
_and_ the complexity of the citation that will give you the complexity  
of re-generating a citation. I’m not really familiar with complexity  
calculation, but shouldn’t this stuff be exponential (or maybe just  
quadratic)?

> But you know whether the content of a certain variable has become part  
> of the output, at least if you keep record. Author-year collapsing can  
> only be reasonably done if for each cited work in a multiple work  
> citation the same variables are printed and the printed variables, with  
> the exception of the year, are identical. Additionally, one should  
> require that the individual citations would generate the same output if  
> the years were identical. Under these circumstances one can collapse the  
> citations by printing any one of the citations and substituting the year  
> for a comma-separated list of years.

consuming the (cached) input could be another solution. I think it  
would be more complicated though. There’s some code for consuming  
variables in the Haskell implementation, but I don’t like this  
approach.

Moreover, by using my idea I can apply some generic programming  
techniques[1], and I like this idea quite a lot (I’ve been struggling  
for quite sometime in the search of a problem that could be addressed  
by using a SYB approach…😉

Andrea

[1] [Computer Science - Vrije Universiteit Amsterdam](http://www.cs.vu.nl/boilerplate/)

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**Author:** ![Stephan\_Tolksdorf](https://avatars.discourse-cdn.com/v4/letter/s/ac8455/32.png) [@Stephan\_Tolksdorf](https://discourse.citationstyles.org/u/Stephan_Tolksdorf)\
**Post date:** [August 4, 2008, 12:08pm UTC](https://discourse.citationstyles.org/t/disambiguate-add-date-option/496/23 "2008-08-04T12:08:24Z")

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Andrea Rossato wrote:\> On Mon, Aug 04, 2008 at 10:02:52AM +0200, Stephan Tolksdorf wrote:

> > My point was that the number is low and only grows with the number of  
> > authors of a work, which always is a low number. So I don’t see a reason  
> > to worry about performance here.
> 
> why not? the problem is not just the number of authors, but the  
> complexity of the style too. You need to re-evaluate the style to  
> re-generate the citation. Is the union of the complexity of the style  
> _and_ the complexity of the citation that will give you the complexity  
> of re-generating a citation. I’m not really familiar with complexity  
> calculation, but shouldn’t this stuff be exponential (or maybe just  
> quadratic)?

I don’t see anything exponential and even if you have O(n^2) or worse  
performance you don’t necessarily run into problems as long as you can  
assume that n is small enough.

Stephan

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**Author:** ![Bruce\_D\_Arcus1](https://avatars.discourse-cdn.com/v4/letter/b/4bbf92/32.png) [@Bruce\_D\_Arcus1](https://discourse.citationstyles.org/u/Bruce_D_Arcus1)\
**Post date:** [August 4, 2008, 1:40pm UTC](https://discourse.citationstyles.org/t/disambiguate-add-date-option/496/24 "2008-08-04T13:40:28Z")

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Might we confirm this assumption?

I’m not sure if this is helpful, but …

Thinking out loud about how I might do this in XSLT, what if an  
intermediate representation included both the shortened version and  
other versions, such that you didn’t need to re-generate? E.g. if we  
break down “Doe et al.” into:

1. the shorted and “final” label string (“Doe et al”)
2. a string that concatenates the author names in full  
(“doe,jane;smith,stephen;sanders,susan”); can be used both for  
sorting, and for comparison to determine if further disambiguation  
might be needed\*

So, for example, if you have more than one item with the author sort  
string “doe,jane;smith,stephen;sanders,susan”, then you know you need  
to group them, and, depending on the style, append a suffix to each.  
This is what I do in my XSLT code\*.

What about adding names? Let’s say we have two references:

“Doe et al” =\> “doe,jane;smith,stephen;sanders,susan”  
“Doe et al” =\> “doe,john;smith,stephen;sanders,susan”

And let’s further say the given names need to be initialized.

You know by comparison that you need to disambiguate. But how? We not  
only need to know what names to add, but how.

How about we first save the formatting rules somewhere so we don’t  
need to look at the style again?

We then iterate through the names until we get to a pair that are not  
the same. In this case, that would be “doe,jane” and “doe,john”. Since  
these are in the fact the first authors, all we need to do is add the  
given names, formatted according to the style.

Bruce

- I have a function in my XSLT code that constructs this string and  
inserts it into an intermediate representation, though I don’t have  
the more complex disambiguation options implemented.

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<div class="post-metadata">

**Author:** ![Andrea\_Rossato1](https://avatars.discourse-cdn.com/v4/letter/a/e47774/32.png) [@Andrea\_Rossato1](https://discourse.citationstyles.org/u/Andrea_Rossato1)\
**Post date:** [August 4, 2008, 4:42pm UTC](https://discourse.citationstyles.org/t/disambiguate-add-date-option/496/25 "2008-08-04T16:42:11Z")

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> > > My point was that the number is low and only grows with the number of  
> > > authors of a work, which always is a low number. So I don’t see a reason  
> > > to worry about performance here.
> > 
> > why not? the problem is not just the number of authors, but the  
> > complexity of the style too. You need to re-evaluate the style to  
> > re-generate the citation.
> 
> Might we confirm this assumption?
> 
> I’m not sure if this is helpful, but …

So far I’m not able to find a counter-example. So I’d call it at leas  
a grounded conjecture.

> What about adding names? Let’s say we have two references:
> 
> “Doe et al” =\> “doe,jane;smith,stephen;sanders,susan”  
> “Doe et al” =\> “doe,john;smith,stephen;sanders,susan”
> 
> And let’s further say the given names need to be initialized.
> 
> You know by comparison that you need to disambiguate. But how? We not  
> only need to know what names to add, but how.
> 
> How about we first save the formatting rules somewhere so we don’t  
> need to look at the style again?
> 
> We then iterate through the names until we get to a pair that are not  
> the same. In this case, that would be “doe,jane” and “doe,john”. Since  
> these are in the fact the first authors, all we need to do is add the  
> given names, formatted according to the style.

I think your encoding is not enough, though. You may need to take into  
account name-as-sort-order and the related sort-separator, which may  
be hidden down a long chain of macro calls.

The solution I’m coding (it is not working yet and I’m not sure it  
will) is this:

In the output I have a type, a list (let’s say of ‘contributors’) I  
can match, which is made up of all possible disambiguation  
possibilities.

That is to say, I have a list of the possible outcome of adding a  
name, a second name, etc. Moreover for each name I have the list of  
the possible outcome, given the style, of the given name  
disambiguation rule.

For instance:  
FC [FN "Rossato, A. " [“Rossato, Andrea”] ,S ", ",FS “et al.” ]  
[[FN "Rossato, A. " [“Rossato, Andrea”] ,S ", ",FN "Pascuzzi, G. " [“Pascuzzi, Giovanni”] ,S ", ",FS “et al.” ],  
[FN "Rossato, A. " [“Rossato, Andrea”] ,S ", ",FN "Pascuzzi, G. " [“Pascuzzi, Giovanni”] ,S ", & ",FN "Caso, R. " [“Caso, Roberto”] ]]]]

After evaluating the style I will search for citations with the same  
FC (FormatedContributors) and the same formatted year and I will start  
disambiguating them till a non colliding version is found.

Andrea

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**Author:** ![Simon\_Kornblith](https://avatars.discourse-cdn.com/v4/letter/s/ce7236/32.png) [@Simon\_Kornblith](https://discourse.citationstyles.org/u/Simon_Kornblith)\
**Post date:** [August 5, 2008, 4:05am UTC](https://discourse.citationstyles.org/t/disambiguate-add-date-option/496/26 "2008-08-05T04:05:36Z")

</div>

This is probably true. I’ve created a ticket to correct these issues  
in Zotero.  
[https://www.zotero.org/trac/ticket/1097](https://www.zotero.org/trac/ticket/1097)

Simon

---

<div class="post-metadata">

**Author:** ![Andrea\_Rossato1](https://avatars.discourse-cdn.com/v4/letter/a/e47774/32.png) [@Andrea\_Rossato1](https://discourse.citationstyles.org/u/Andrea_Rossato1)\
**Post date:** [August 5, 2008, 7:53pm UTC](https://discourse.citationstyles.org/t/disambiguate-add-date-option/496/27 "2008-08-05T19:53:39Z")

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> You know by comparison that you need to disambiguate.

No, you do not.

Today I lost myself into the complexity of disambiguation and I think  
I hit a problem which makes all this disambiguation even more  
problematic.

The problem is the locator. The output of a citation with a locator is  
not comparable with the citation of the same reference, but without  
locator. And you cannot remove the locator from a formatted citation,  
since you cannot know how it will look like.

And evaluating a citation with the locator variable unset will not  
help you, since the output could differ a lot (think about \<if

> ) and disambiguating this one could be totally different from  
> disambiguating the citation with the locator.

The only solution I can think is this one: you disambiguate if two  
citations share the same group of names, equally formatted, and the  
same year, equally formatted. The problem is that I will disambiguate  
even if the citations, which have the same names and year, are already  
disambiguated (by the title or whatever else - an edition number?).

I know that you may think these issues are mostly theoretical since  
I’m considering eventualities with a low probability of occurrence.  
Nonetheless I think that if an implementation is not able to evaluate  
all syntactically correct expressions because of a language feature,  
maybe there could be an issue with the language feature itself.

Or maybe I’m just too fed up with this problem and I need to step back  
and let sleep on the back of my mind for a few days. Maybe I’m just  
wrong.

Andrea

---

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**Author:** ![Bruce\_D\_Arcus1](https://avatars.discourse-cdn.com/v4/letter/b/4bbf92/32.png) [@Bruce\_D\_Arcus1](https://discourse.citationstyles.org/u/Bruce_D_Arcus1)\
**Post date:** [August 5, 2008, 8:05pm UTC](https://discourse.citationstyles.org/t/disambiguate-add-date-option/496/28 "2008-08-05T20:05:19Z")

</div>

> > You know by comparison that you need to disambiguate.
> 
> No, you do not.

Sure you do; you know that if specified, you need to add the year  
suffix. In author-date styles, that’s the most common and important  
one.

There are different kinds of disambiguation here, so it might make  
sense to account for that in the code.

> Today I lost myself into the complexity of disambiguation and I think  
> I hit a problem which makes all this disambiguation even more  
> problematic.
> 
> The problem is the locator. The output of a citation with a locator is  
> not comparable with the citation of the same reference, but without  
> locator. And you cannot remove the locator from a formatted citation,  
> since you cannot know how it will look like.

So don’t compare the formatted output of the entire citation.

> And evaluating a citation with the locator variable unset will not  
> help you, since the output could differ a lot (think about \<if
> 
> > ) and disambiguating this one could be totally different from  
> > disambiguating the citation with the locator.
> 
> The only solution I can think is this one: you disambiguate if two  
> citations share the same group of names, equally formatted, and the  
> same year, equally formatted.

That’s basically what I’m suggesting.

> The problem is that I will disambiguate  
> even if the citations, which have the same names and year, are already  
> disambiguated (by the title or whatever else - an edition number?).

Not following you here.

> I know that you may think these issues are mostly theoretical since  
> I’m considering eventualities with a low probability of occurrence.  
> Nonetheless I think that if an implementation is not able to evaluate  
> all syntactically correct expressions because of a language feature,  
> maybe there could be an issue with the language feature itself.

I don’t think this is really a problem with CSL; it’s a function of  
the ugly eccentricities of citation formatting.

> Or maybe I’m just too fed up with this problem and I need to step back  
> and let sleep on the back of my mind for a few days.

That might make sense.

I hope Stephen will find some time to experiment with this, and maybe  
offer some concrete input.

Bruce

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<div class="post-metadata">

**Author:** ![Andrea\_Rossato1](https://avatars.discourse-cdn.com/v4/letter/a/e47774/32.png) [@Andrea\_Rossato1](https://discourse.citationstyles.org/u/Andrea_Rossato1)\
**Post date:** [August 5, 2008, 8:49pm UTC](https://discourse.citationstyles.org/t/disambiguate-add-date-option/496/29 "2008-08-05T20:49:08Z")

</div>

> > The problem is that I will disambiguate  
> > even if the citations, which have the same names and year, are already  
> > disambiguated (by the title or whatever else - an edition number?).
> 
> Not following you here.

If 2 citations have the same group of names and the same year - the  
only elements of a formatted citation you can compare -, then you must  
apply the disambiguation rules. Even if the citation style for that  
reference type may include other strings (which would be enough for  
disambiguation).

> > I know that you may think these issues are mostly theoretical since  
> > I’m considering eventualities with a low probability of occurrence.  
> > Nonetheless I think that if an implementation is not able to evaluate  
> > all syntactically correct expressions because of a language feature,  
> > maybe there could be an issue with the language feature itself.
> 
> I don’t think this is really a problem with CSL; it’s a function of  
> the ugly eccentricities of citation formatting.

Which could also mean that the above solution is the best we can  
achieve.

Andrea

---

<div class="post-metadata">

**Author:** ![Simon\_Kornblith](https://avatars.discourse-cdn.com/v4/letter/s/ce7236/32.png) [@Simon\_Kornblith](https://discourse.citationstyles.org/u/Simon_Kornblith)\
**Post date:** [August 5, 2008, 9:24pm UTC](https://discourse.citationstyles.org/t/disambiguate-add-date-option/496/30 "2008-08-05T21:24:04Z")

</div>

I think the disambiguate conditional should work here, at least in  
theory, although I haven’t tested this particular use of it with the  
Zotero code.

Simon

---

<div class="post-metadata">

**Author:** ![Elena\_Razlogova](https://avatars.discourse-cdn.com/v4/letter/e/c89c15/32.png) [@Elena\_Razlogova](https://discourse.citationstyles.org/u/Elena_Razlogova)\
**Post date:** [August 5, 2008, 9:47pm UTC](https://discourse.citationstyles.org/t/disambiguate-add-date-option/496/31 "2008-08-05T21:47:47Z")

</div>

> > > Since the date should only be added if there are multiple interviews  
> > > with the same subject and interviewer, there should be something  
> > > like  
> > > disambiguate-add-date option in CSL. It would be relevant to letters  
> > > with the same recipient and sender but different dates. Would it be  
> > > possible to add this option?
> > 
> > This makes sense, but there’s a little problem related to the  
> > previous  
> > discussion with Andrea: how would we specify the formatting of the  
> > date?
> > 
> > I’m not really clear: would the disambiguate prefix on the  
> > conditional  
> > work? I wasn’t the one the added the following, and so I’m not really  
> > clear:
> > 
> > ## If text inside an block can be used to
> > 
> > ## differentiate two otherwise identical citations, it will be
> > 
> > added.
> > 
> > ## If the citations remain identical after its addition, it will not
> > 
> > ## be added.
> 
> I think the disambiguate conditional should work here, at least in  
> theory, although I haven’t tested this particular use of it with the  
> Zotero code.

Does that mean we don’t need an option then? MLA style uses this code  
below, and it seems to work:

Best,  
Elena

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<div class="post-metadata">

**Author:** ![Elena\_Razlogova](https://avatars.discourse-cdn.com/v4/letter/e/c89c15/32.png) [@Elena\_Razlogova](https://discourse.citationstyles.org/u/Elena_Razlogova)\
**Post date:** [August 5, 2008, 10:01pm UTC](https://discourse.citationstyles.org/t/disambiguate-add-date-option/496/32 "2008-08-05T22:01:29Z")

</div>

Never mind. This doesn’t work:

```
     <else-if position="subsequent">
       <group delimiter=", ">
         <text macro="contributors-short"/>
         <text macro="title-short"/>
           <choose>
             <if disambiguate="true">
               <text macro="issued"/>
             </if>
           </choose>
         <text macro="point-locators-subsequent"/>
       </group>
     </else-if>

```

This theoretically should add a date after title if the citation is  
the same, but it doesn’t.  
Best,  
Elena

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