Support pdfMML annotations in LuaTeX

luamml-pdf.sty

@@ -51,7 +51,7 @@
 %   #2 annotation
 %   #3 nodes to be annotated
 \int_new:N \g__luamml_annotation_id_int
-\cs_new_protected:Npn \luamml_pdf_annotate:nnn #1#2#3 {
+\cs_new_protected:Npn \luamml_annotate:nen #1#2#3 {
   \int_gincr:N \g__luamml_annotation_id_int
   \iow_shipout_x:Nx \l__luamml_pdf_stream {
     \tl_to_str:e {
@@ -71,7 +71,7 @@
 %   #1 annotation
 %   #2 nodes to be annotated
 % THIS VERSION IS SIGNIFICANTLY SLOWER
-\cs_new_protected:Npn \luamml_pdf_annotate:nn #1#2 {
+\cs_new_protected:Npn \luamml_annotate:en #1#2 {
   \int_gincr:N \g__luamml_annotation_id_int
   \iow_shipout_x:Nx \l__luamml_pdf_stream {
     \tl_to_str:e {

luamml-tex-annotate.lua

@@ -0,0 +1,100 @@
+local nest = tex.nest
+
+local properties = node.get_properties_table()
+
+local mark_environment = {}
+
+local function annotate()
+  local annotation, err = load( 'return {'
+      .. token.scan_argument()
+    .. '}', nil, 't', mark_environment)
+  if not annotation then
+    tex.error('Error while parsing LuaMML annotation', {err})
+    return 0
+  end
+  annotation = annotation()
+  local nesting = nest.top
+  local props = properties[nesting.head]
+  local current = props and props.luamml__annotate_context
+  if current then
+    current, props.luamml__annotate_context = current.head, current.prev
+  else
+    tex.error('Mismatched LuaMML annotation',
+      {'Something odd happened. Maybe you forgot braces around an annotated symbol in a subscript or superscript?'})
+    return 0
+  end
+  local after = nesting.tail
+  local count, offset = 0, annotation.offset
+  local marked
+  if current == after then
+    tex.error'Empty LuaMML annotation'
+  else
+    repeat
+      current = current.next
+      count = count + 1
+      if count == offset then
+        marked = current
+      elseif offset or current ~= after then
+        local props = properties[current]
+        if not props then
+          props = {}
+          properties[current] = props
+        end
+        props.mathml_table, props.mathml_core = nil, false
+      end
+    until current == after
+    if offset and not marked then
+      tex.error'Invalid offset in LuaMML annotation'
+    end
+    marked = marked or current
+    if annotation.nucleus then
+      marked = marked.nucleus
+    end
+    if marked then
+      local props = properties[marked]
+      if not props then
+        props = {}
+        properties[marked] = props
+      end
+      props.mathml_core = annotation.core
+    else
+      tex.error'Unable to annotate nucleus of node without nucleus'
+    end
+  end
+  return count
+end
+
+local funcid = luatexbase.new_luafunction'__luamml_annotate_begin:'
+token.set_lua('__luamml_annotate_begin:', funcid, 'protected')
+lua.get_functions_table()[funcid] = function()
+  local top = nest.top
+  local temp = top.head
+  local props = properties[temp]
+  if not props then
+    props = {}
+    properties[temp] = props
+  end
+  props.luamml__annotate_context = {
+    prev = props.luamml__annotate_context,
+    head = top.tail,
+  }
+end
+
+funcid = luatexbase.new_luafunction'__luamml_annotate_end:we'
+token.set_lua('__luamml_annotate_end:we', funcid, 'protected')
+lua.get_functions_table()[funcid] = function()
+  local count = token.scan_int()
+  local real_count = annotate()
+  if count ~= real_count then
+    tex.error('Incorrect count in LuaMML annotation', {
+        'A LuaMML annotation was discovered with an explicit count \z
+        which was not the same as the number of top-level nodes annotated.',
+        string.format('This can be fixed by changing the supplied count from %i to %i \z
+          or by omitting the count value entirely.', count, real_count)
+    })
+  end
+end
+
+funcid = luatexbase.new_luafunction'__luamml_annotate_end:e'
+token.set_lua('__luamml_annotate_end:e', funcid, 'protected')
+lua.get_functions_table()[funcid] = annotate

luamml-tex.lua

@@ -113,6 +113,8 @@ lua.get_functions_table()[funcid] = function()
   mlist_result = nil
 end
 
+require'luamml-tex-annotate'
+
 return {
   save_result = save_result,
 }

luamml.sty

@@ -19,6 +19,20 @@
   \tl_set:Nn \l__luamml_filename_tl
 }
 
+
+\cs_new_protected:Npn \luamml_annotate:nen #1#2#3 {
+  \__luamml_annotate_begin:
+    #3
+    \__luamml_annotate_end:we \tex_numexpr:D #1 \scan_stop: {#2}
+}
+
+\cs_new_protected:Npn \luamml_annotate:en #1#2 {
+  \__luamml_annotate_begin:
+    #2
+  \__luamml_annotate_end:e {#1}
+}
+
+
 \cs_new:Npn \__luamml_patch_package:nn #1 #2 {
   \@ifpackageloaded {#1} {#2} {
     \hook_gput_code:nnn {package/after/#1} {luamml} {#2}

test_pdf.tex

@@ -9,9 +9,9 @@
 \cs_set_eq:NN \WriteoutFormula \luamml_pdf_write:
 \NewDocumentCommand\AnnotateFormula{ o m m }{%
   \IfValueTF{#1}{%
-    \luamml_pdf_annotate:nnn{#1}%
+    \luamml_annotate:nnn{#1}%
   }{
-    \luamml_pdf_annotate:nn
+    \luamml_annotate:nn
   }{#2}{#3}
 }
 \ExplSyntaxOff