Matrix and array support (requires array package)

luamml-amsmath.lua

@@ -52,7 +52,6 @@ lua.get_functions_table()[funcid] = function()
       chars[#chars+1] = 0x20
     elseif id == node.id'kern' then
     else
-      print(n)
       texio.write_nl'WARNING: Unsupported node in tag dropped'
     end
   end

luamml-array.lua

@@ -0,0 +1,87 @@
+local write_xml = require'luamml-xmlwriter'
+local make_root = require'luamml-convert'.make_root
+local save_result = require'luamml-tex'.save_result
+local store_column = require'luamml-table'.store_column
+local store_tag = require'luamml-table'.store_tag
+local get_table = require'luamml-table'.get_table
+
+local properties = node.get_properties_table()
+
+local funcid = luatexbase.new_luafunction'__luamml_array_add_list_to_row:'
+token.set_lua('__luamml_array_add_list_to_row:', funcid, 'protected')
+lua.get_functions_table()[funcid] = function()
+  -- TODO: Error handling etc
+  -- local box = token.scan_int()
+  local startmath
+  local preskip
+  local postskip
+  local prestretch = 0 -- Not one since overflowing content protrudes right
+  local stretch = {0, 0, 0, 0, 0}
+  local n = tex.nest.top.head.next
+  local func, ctx, n = node.traverse(tex.nest.top.head.next)
+  while true do
+    local id, sub n, id, sub = func(ctx, n)
+    if not n then break end
+    if node.id'math' == id then
+      if sub == 0 then
+        if startmath then
+          texio.write_nl'Multiple formulas detected in array field'
+        end
+        startmath = n
+        for i=2, 5 do
+          if stretch[i] ~= 0 then
+            prestretch = i
+          end
+        end
+        n = node.end_of_math(n)
+      end
+    elseif node.id'glue' == id then
+      stretch[n.stretch_order+1] = stretch[n.stretch_order+1] + n.stretch
+    elseif node.id'rule' == id then
+    else
+      texio.write_nl'Foreign nodes detected in array field'
+    end
+  end
+  if startmath then
+    local poststretch
+    for i=1, 5 do
+      if stretch[i] ~= 0 then
+        poststretch = i
+      end
+    end
+    store_column(startmath).columnalign = prestretch < poststretch and 'left' or prestretch > poststretch and 'right' or nil -- or 'center' -- center is already default
+  else
+    texio.write_nl'Formula missing in array field'
+  end
+end
+
+local saved_array
+
+funcid = luatexbase.new_luafunction'__luamml_array_finalize_array:'
+token.set_lua('__luamml_array_save_array:', funcid)
+lua.get_functions_table()[funcid] = function()
+  -- TODO: Error handling etc.
+  local colsep = tex.dimen['col@sep']
+  saved_array = get_table()
+  if colsep ~= 0 then
+    saved_array = {[0] = 'mpadded',
+      width = string.format('%+.3fpt', 2*colsep/65781.76),
+      lspace = string.format('%+.3fpt', colsep/65781.76),
+      saved_array
+    }
+  end
+end
+
+funcid = luatexbase.new_luafunction'__luamml_array_finalize_array:'
+token.set_lua('__luamml_array_finalize_array:', funcid)
+lua.get_functions_table()[funcid] = function()
+  -- TODO: Error handling etc.
+  local nucl = tex.nest.top.tail.nucleus
+  local props = properties[nucl]
+  if not props then
+    props = {}
+    properties[nucl] = props
+  end
+  props.mathml_table = saved_array
+  saved_array = nil
+end

luamml-convert.lua

@@ -45,7 +45,7 @@ local function delim_to_table(delim)
   if props then return props end
   local char = delim.small_char
   if char == 0 then
-    return {[0] = 'mspace', width = string.format("%.2fpt", tex.nulldelimiterspace/65781.76)}, space_like
+    return {[0] = 'mspace', width = string.format("%.3fpt", tex.nulldelimiterspace/65781.76)}, space_like
   else
     local fam = delim.small_fam
     char = remap_lookup[fam << 21 | char]
@@ -277,10 +277,10 @@ local function space_to_table(amount, sub, cur_style)
   if amount == 0 then return end
   if sub == 99 then -- TODO magic number
     -- 18*2^16=1179648
-    return {[0] = 'mspace', width = string.format("%.2fem", amount/1179648)}, space_like
+    return {[0] = 'mspace', width = string.format("%.3fem", amount/1179648)}, space_like
   else
     -- 65781.76=tex.sp'100bp'/100
-    return {[0] = 'mspace', width = string.format("%.2fpt", amount/65781.76)}, space_like
+    return {[0] = 'mspace', width = string.format("%.3fpt", amount/65781.76)}, space_like
   end
 end
 

luamml-patches-array.sty

@@ -0,0 +1,43 @@
+\ProvidesExplPackage {luamml-patches-array} {2021-04-23} {0.0.1-alpha}
+  {Feel free to add a description here}
+
+\lua_now:n { require'luamml-array' }
+
+\cs_new:Npn \__luamml_array_dollarend_array: {
+  \luamml_flag_save:
+  $
+  \__luamml_array_add_list_to_row:
+}
+
+\cs_new_eq:NN \luamml@d@llarend@array \__luamml_array_dollarend_array:
+\cs_set:Npn \array {
+  \col@sep \arraycolsep
+  \def \d@llarbegin { $ }
+  \let \d@llarend \luamml@d@llarend@array
+  \def \@halignto {}
+  \@tabarray
+}
+\cs_set:Npn \endarray {
+  \crcr
+  \__luamml_array_save_array:
+  \egroup
+  \egroup
+  \__luamml_array_finalize_array:
+  \@arrayright
+  \gdef \@preamble {}
+}
+\cs_set:Npn \endalign {
+  \math@cr
+  \black@ \totwidth@
+  \__luamml_amsmath_finalize_table:
+  \egroup
+  \ifingather@
+    \restorealignstate@
+    \egroup
+    \nonumber
+    \ifnum0=‘{\fi\iffalse}\fi
+  \else
+    $$
+  \fi
+  \ignorespacesafterend
+}

luamml-table.lua

@@ -34,6 +34,7 @@ local function store_column(startmath, display)
     mml = {[0] = 'mtd', mml}
   end
   table.insert(store_get_row(), mml)
+  return mml
 end
 
 local function store_tag(xml)

luamml.sty

@@ -18,4 +18,15 @@
   \int_set:Nn \l__luamml_flag_int { 6 }
 }
 
-\RequirePackage { luamml-patches-amsmath }
+\cs_new:Npn \__luamml_patch_package:nn #1 #2 {
+  \@ifpackageloaded {#1} {#2} {
+    \hook_gput_code:nnn {package/after/#1} {luamml} {#2}
+  }
+}
+\cs_new:Npn \__luamml_patch_package:n #1 {
+  \__luamml_patch_package:nn {#1} {
+    \RequirePackage { luamml-patches-#1 }
+  }
+}
+\__luamml_patch_package:n {amsmath}
+\__luamml_patch_package:n {array}