diff -r d4b0773f5e06 -r 3ac53da03439 markdown_it.lua
--- a/markdown_it.lua	Mon Jul 06 13:34:06 2020 -0500
+++ b/markdown_it.lua	Fri Jul 17 10:00:47 2020 -0500
@@ -2,6 +2,17 @@
 
 local io = require('io')
 local os = require('os')
+local path = require('mypath')
+local lfs = require('lfs')
+
+function markdown_it.katex_config(env)
+    katex_config = path.join(env.paths.tmpl, "katex_config.json")
+    if lfs.attributes(katex_config) then
+        return katex_config
+    else
+        return nil
+    end
+end
 
 function markdown_it.markdown(str, env)
     -- Lua doesn't have bidirectional pipes without the posix library.
@@ -12,6 +23,11 @@
     cmd = string.format("node '%s/markdown_it.js' '%s'",
                         env.paths.lgen_location,
                         tmpname)
+    -- Provide TEMPLATE_PATH/katex_config.json if it exists
+    katex_config = markdown_it.katex_config(env)
+    if katex_config then
+        cmd = cmd .. " '" .. katex_config .. "'"
+    end
     io.stdout:write('Executing ' .. cmd .. '\n')
     h = io.popen(cmd, 'r')
     result = h:read("*a")
@@ -20,4 +36,11 @@
     return result
 end
 
+function markdown_it.add_deps(deps, env)
+    katex_config = markdown_it.katex_config(env)
+    if katex_config then
+        table.insert(deps, katex_config)
+    end
+end
+
 return markdown_it