diff --git a/.gitignore b/.gitignore
index d741dbbc2..cb19a30b0 100644
--- a/.gitignore
+++ b/.gitignore
@@ -14,3 +14,4 @@
 build/*
 **/*.o
 **/*.so
+tex/generic/pgf/pgf.revision.tex
diff --git a/doc/generic/pgf/lib/examplescasfinder.lua b/doc/generic/pgf/lib/examplescasfinder.lua
index 39f1b2939..ad1832020 100644
--- a/doc/generic/pgf/lib/examplescasfinder.lua
+++ b/doc/generic/pgf/lib/examplescasfinder.lua
@@ -25,7 +25,7 @@ local C, P, V, Ct, Cf, Cg = lpeg.C, lpeg.P, lpeg.V, lpeg.Ct, lpeg.Cf, lpeg.Cg
 --   end
 -- )
 
-local tostring = UNIT_TESTING and require "ml".tstring or nil
+-- local tostring = UNIT_TESTING and require "ml".tstring or nil
 
 local finder = {}
 
@@ -74,18 +74,8 @@ finder.grammar =
   exentry = str * P(",") ^ -1
 }
 
-local function preamble(options)
-  local p = SP * P "preamble" * SP * "=" * SP * C(P(1) ^ 1)
-  local matches = p:match(u.get_string(options))
-  local table = {}
-  if matches then
-    table.preamble = matches
-  end
-  return table
-end
-
 function finder.get_options(e)
-  return e.options and preamble(e.options) or {}
+  return e.options and u.preamble(e.options) or {}
 end
 
 function finder.get_content(e)
@@ -184,10 +174,11 @@ local test_case4 =
 do
   local matches = finder.grammar:match(test_case4)
   assert(#matches == 2)
-  assert(
-    u.strip(u.get_string(matches[1].options)) ==
-      [[preamble={\usetikzlibrary{graphs,graphdrawing} \usegdlibrary{force}}]]
-  )
+  local expected_options = [[preamble={\usetikzlibrary{graphs,graphdrawing} \usegdlibrary{force}}]]
+  assert(u.strip(u.get_string(matches[1].options)) == expected_options)
+  local t = u.preamble(expected_options)
+  assert(t.preamble == [[\usetikzlibrary{graphs,graphdrawing} \usegdlibrary{force}]])
+
   assert(
     u.strip(u.get_string(matches[1].code)) ==
       [[\tikz \graph [spring electrical layout, horizontal=0 to 1]
diff --git a/doc/generic/pgf/lib/examplesfinder.lua b/doc/generic/pgf/lib/examplesfinder.lua
index c36f095b7..1916246a7 100644
--- a/doc/generic/pgf/lib/examplesfinder.lua
+++ b/doc/generic/pgf/lib/examplesfinder.lua
@@ -81,18 +81,8 @@ finder.grammar =
   codekv = Cg(C("code") * SP * "=" * str)
 }
 
-local function preamble(options)
-  local p = SP * P "preamble" * SP * "=" * SP * C(P(1) ^ 1)
-  local matches = p:match(u.get_string(options))
-  local table = {}
-  if matches then
-    table.preamble = matches
-  end
-  return table
-end
-
 function finder.get_options(e)
-  return e.options and preamble(e.options) or {}
+  return e.options and u.preamble(e.options) or {}
 end
 
 function finder.get_content(e)
diff --git a/doc/generic/pgf/lib/examplewithoptionfinder.lua b/doc/generic/pgf/lib/examplewithoptionfinder.lua
index 87068ae9c..c9ca11c28 100644
--- a/doc/generic/pgf/lib/examplewithoptionfinder.lua
+++ b/doc/generic/pgf/lib/examplewithoptionfinder.lua
@@ -64,7 +64,7 @@ local function preamble(options)
     local matches = p:match(options)
     local table = {}
     if matches then
-        table.preamble = matches
+        table.preamble = u.strip_braces(matches)
     end
     return table
 end
@@ -135,7 +135,7 @@ example {
 
 do
     local matches = finder.grammar:match(test_case2)
-    print("#matches:", #matches)
+    assert(#matches == 2)
     assert(u.strip(finder.get_options(matches[1]).preamble) == [[first example preamble]])
     assert(u.strip(finder.get_content(matches[1])) == [[first example code]])
     assert(not finder.get_options(matches[2]).preamble)
diff --git a/doc/generic/pgf/lib/utils.lua b/doc/generic/pgf/lib/utils.lua
index 0ce0b80c2..7d8898e32 100644
--- a/doc/generic/pgf/lib/utils.lua
+++ b/doc/generic/pgf/lib/utils.lua
@@ -207,4 +207,14 @@ function u.walk(sourcedir, targetdir, finder)
     end
 end
 
+function u.preamble(options)
+    local p = u.SP * lpeg.P "preamble" * u.SP * "=" * u.SP * lpeg.C(lpeg.P(1) ^ 1)
+    local matches = p:match(u.get_string(options))
+    local table = {}
+    if matches then
+        table.preamble = u.strip_braces(matches)
+    end
+    return table
+end
+
 return utils