Dear Hans and all contributors,

I really appreciate ConTeXt for the right way to obtain high quality documents. I'm a theoretical physicist and I'm going to write a book. I think ConTeXt is the right choice to work with a number of formulas, figures and cross-references. The visual quality of formulas is better than in regular LaTeX. The new feature with formula autosplitting looks also very promising. For me it is important to obtain the high quality without a lot of manual tweaks of each formula for each given document format and figure placement.

However, I have found a problem with references if I compile one component only. The references to formulas in other components have wrong prefixes, e.g. (2.1) instead of (3.1). Needless to say, the right formula references are very important.

I started looking into this issue. The references to other components are taken from the whole product as from an external document. It turned out that this is a general problem with references with prefixes to external documents. The prefix is stored in a tuc file as a reference to a section as a sequential number of the header in the document. As a result, the prefix from the external document is calculated using the structure of the current document.

Here is the MWE, which consists of two files:

\defineenumeration[remark][prefix=yes, prefixsegments=chapter:section]


Equations: \in[eq1], \in[eq2], \in[eq3], \in[eq4]

Sections: \in[sec1], \in[sec2], \in[sec3], \in[sec4]

Chapters: \in[chap1], \in[chap2], \in[chap3], \in[chap4]

Remarks: \in[remark1], \in[remark2]


\placeformula[eq1]\startformula x = y\stopformula
\placeformula[eq1]\startformula x = y\stopformula
\placeformula[eq2]\startformula x = y\stopformula



\placeformula[eq3]\startformula x = y\stopformula
\placeformula[eq4]\startformula x = y\stopformula





Equations: \in[foo::eq1], \in[foo::eq2], \in[foo::eq3], \in[foo::eq4]

Sections: \in[foo::sec1], \in[foo::sec2], \in[foo::sec3], \in[foo::sec4]

Chapters: \in[foo::chap1], \in[foo::chap2], \in[foo::chap3], \in[foo::chap4]

Remarks: \in[foo::remark1], \in[foo::remark2]

% any chapters and sections here


It is expected to have the same first page on these documents:

Equations: 1.1, 2.2, A.1, A.2
Sections: 2.1, 2.2, A.1, A.2
Chapters: 1, 2, A, B
Remarks: A.2.1, A.2.2

However, the bar.tex produces wrong prefixes to formulas and remarks. The output depends on the document structure of bar.tex, not foo.tex.

I started looking into the source code. Thanks to lua, it is not a big deal to track the problem. The prefixdata is complemented by the sectiondata after the loading the tuc file. So, the question is: is it possible to store the full prefixdata with all necessary prefix numbers in the tuc file? Here is my proposal to change the source code:

--- strc-lst-old.lmt    2023-01-29 11:30:15.610309948 +0300
+++ strc-lst.lmt        2023-01-29 12:10:08.864228923 +0300
@@ -266,6 +266,16 @@
     if r and not r.section then
         r.section = structures.sections.currentid()
+    -- store sectiondata in prefixdata (necessary for external files)
+    if t.prefixdata and r.section then
+        local sectiondata = structures.sections.collected[r.section]
+        if sectiondata then
+            for k, v in next, sectiondata do
+                t.prefixdata[k] = v
+            end
+        end
+    end
+    --
     local b = r and t.block
     if r and not b then
         local s = r.section

--- strc-ref-old.lmt    2023-01-29 11:30:15.823643904 +0300
+++ strc-ref.lmt        2023-01-29 12:07:45.697109862 +0300
@@ -2318,7 +2318,17 @@
     if data then
         numberdata = lists.reordered(data) -- data.numberdata
         if numberdata then
-            helpers.prefix(data,prefixspec)
+            -- helpers.prefix(data,prefixspec)
+            -- use the actual numbers from prefixdata
+            local prefixdata = data.prefixdata
+            if prefixdata then
+                -- adapted from helpers.prefix (not sure)
+                if (prefixspec and prefixspec == no) or prefixdata.prefix == no then
+                    prefixdata = false
+                end
+                sections.typesetnumber(prefixdata,"prefix", prefixspec or false, prefixdata)
+            end
+            --
             local useddata = data.useddata

After this small change, all the references are correct. However, I'm quite new to ConTeXt, so maybe here are some caveats. It would be great to fix the references to formulas, especially for the forthcoming document about maths.

Best regards,
Yaroslav Beltukov