Merge pull request #374 from phi-gamma/master

lastest feature code

1 files changed, 344 insertions, 282 deletions

diff --git a/src/fontloader/runtime/fontloader-reference.lua b/src/fontloader/runtime/fontloader-reference.lua
index 13c45aa..4cefe9a 100644
--- a/src/fontloader/runtime/fontloader-reference.lua
+++ b/src/fontloader/runtime/fontloader-reference.lua
@@ -1,6 +1,6 @@
 -- merged file : c:/data/develop/context/sources/luatex-fonts-merged.lua
 -- parent file : c:/data/develop/context/sources/luatex-fonts.lua
--- merge date  : 07/25/16 21:49:08
+-- merge date  : 07/30/16 00:26:47
 
 do -- begin closure to overcome local limits and interference
 
@@ -5722,6 +5722,7 @@ local next,tostring,rawget=next,tostring,rawget
 local format,match,lower,gsub,find=string.format,string.match,string.lower,string.gsub,string.find
 local sort,insert,concat,sortedkeys,serialize,fastcopy=table.sort,table.insert,table.concat,table.sortedkeys,table.serialize,table.fastcopy
 local derivetable=table.derive
+local ioflush=io.flush
 local trace_defining=false trackers.register("fonts.defining",function(v) trace_defining=v end)
 local trace_scaling=false trackers.register("fonts.scaling",function(v) trace_scaling=v end)
 local report_defining=logs.reporter("fonts","defining")
@@ -6547,134 +6548,233 @@ setmetatableindex(formats,function(t,k)
   end
   return rawget(t,file.suffix(l))
 end)
-local locations={}
-local function setindeed(mode,target,group,name,action,position)
-  local t=target[mode]
-  if not t then
-    report_defining("fatal error in setting feature %a, group %a, mode %a",name,group,mode)
-    os.exit()
-  elseif position then
-    insert(t,position,{ name=name,action=action })
-  else
-    for i=1,#t do
-      local ti=t[i]
-      if ti.name==name then
-        ti.action=action
-        return
+do
+  local function setindeed(mode,target,group,name,action,position)
+    local t=target[mode]
+    if not t then
+      report_defining("fatal error in setting feature %a, group %a, mode %a",name,group,mode)
+      os.exit()
+    elseif position then
+      insert(t,position,{ name=name,action=action })
+    else
+      for i=1,#t do
+        local ti=t[i]
+        if ti.name==name then
+          ti.action=action
+          return
+        end
       end
+      insert(t,{ name=name,action=action })
     end
-    insert(t,{ name=name,action=action })
   end
-end
-local function set(group,name,target,source)
-  target=target[group]
-  if not target then
-    report_defining("fatal target error in setting feature %a, group %a",name,group)
-    os.exit()
-  end
-  local source=source[group]
-  if not source then
-    report_defining("fatal source error in setting feature %a, group %a",name,group)
-    os.exit()
-  end
-  local node=source.node
-  local base=source.base
-  local position=source.position
-  if node then
-    setindeed("node",target,group,name,node,position)
-  end
-  if base then
-    setindeed("base",target,group,name,base,position)
-  end
-end
-local function register(where,specification)
-  local name=specification.name
-  if name and name~="" then
-    local default=specification.default
-    local description=specification.description
-    local initializers=specification.initializers
-    local processors=specification.processors
-    local manipulators=specification.manipulators
-    local modechecker=specification.modechecker
-    if default then
-      where.defaults[name]=default
+  local function set(group,name,target,source)
+    target=target[group]
+    if not target then
+      report_defining("fatal target error in setting feature %a, group %a",name,group)
+      os.exit()
     end
-    if description and description~="" then
-      where.descriptions[name]=description
+    local source=source[group]
+    if not source then
+      report_defining("fatal source error in setting feature %a, group %a",name,group)
+      os.exit()
     end
-    if initializers then
-      set('initializers',name,where,specification)
+    local node=source.node
+    local base=source.base
+    local position=source.position
+    if node then
+      setindeed("node",target,group,name,node,position)
     end
-    if processors then
-      set('processors',name,where,specification)
-    end
-    if manipulators then
-      set('manipulators',name,where,specification)
+    if base then
+      setindeed("base",target,group,name,base,position)
     end
-    if modechecker then
-      where.modechecker=modechecker
+  end
+  local function register(where,specification)
+    local name=specification.name
+    if name and name~="" then
+      local default=specification.default
+      local description=specification.description
+      local initializers=specification.initializers
+      local processors=specification.processors
+      local manipulators=specification.manipulators
+      local modechecker=specification.modechecker
+      if default then
+        where.defaults[name]=default
+      end
+      if description and description~="" then
+        where.descriptions[name]=description
+      end
+      if initializers then
+        set('initializers',name,where,specification)
+      end
+      if processors then
+        set('processors',name,where,specification)
+      end
+      if manipulators then
+        set('manipulators',name,where,specification)
+      end
+      if modechecker then
+        where.modechecker=modechecker
+      end
     end
   end
-end
-constructors.registerfeature=register
-function constructors.getfeatureaction(what,where,mode,name)
-  what=handlers[what].features
-  if what then
-    where=what[where]
-    if where then
-      mode=where[mode]
-      if mode then
-        for i=1,#mode do
-          local m=mode[i]
-          if m.name==name then
-            return m.action
+  constructors.registerfeature=register
+  function constructors.getfeatureaction(what,where,mode,name)
+    what=handlers[what].features
+    if what then
+      where=what[where]
+      if where then
+        mode=where[mode]
+        if mode then
+          for i=1,#mode do
+            local m=mode[i]
+            if m.name==name then
+              return m.action
+            end
           end
         end
       end
     end
   end
-end
-local newhandler={}
-constructors.handlers=newhandler 
-constructors.newhandler=newhandler
-local function setnewhandler(what) 
-  local handler=handlers[what]
-  if not handler then
-    handler={}
-    handlers[what]=handler
+  local newfeatures={}
+  constructors.newfeatures=newfeatures 
+  constructors.features=newfeatures
+  local function setnewfeatures(what)
+    local handler=handlers[what]
+    local features=handler.features
+    if not features then
+      local tables=handler.tables   
+      local statistics=handler.statistics 
+      features=allocate {
+        defaults={},
+        descriptions=tables and tables.features or {},
+        used=statistics and statistics.usedfeatures or {},
+        initializers={ base={},node={} },
+        processors={ base={},node={} },
+        manipulators={ base={},node={} },
+      }
+      features.register=function(specification) return register(features,specification) end
+      handler.features=features 
+    end
+    return features
   end
-  return handler
+  setmetatable(newfeatures,{
+    __call=function(t,k) local v=t[k] return v end,
+    __index=function(t,k) local v=setnewfeatures(k) t[k]=v return v end,
+  })
 end
-setmetatable(newhandler,{
-  __call=function(t,k) local v=t[k] return v end,
-  __index=function(t,k) local v=setnewhandler(k) t[k]=v return v end,
-})
-local newfeatures={}
-constructors.newfeatures=newfeatures 
-constructors.features=newfeatures
-local function setnewfeatures(what)
-  local handler=handlers[what]
-  local features=handler.features
-  if not features then
-    local tables=handler.tables   
-    local statistics=handler.statistics 
-    features=allocate {
-      defaults={},
-      descriptions=tables and tables.features or {},
-      used=statistics and statistics.usedfeatures or {},
-      initializers={ base={},node={} },
-      processors={ base={},node={} },
-      manipulators={ base={},node={} },
-    }
-    features.register=function(specification) return register(features,specification) end
-    handler.features=features 
+do
+  local newhandler={}
+  constructors.handlers=newhandler 
+  constructors.newhandler=newhandler
+  local function setnewhandler(what) 
+    local handler=handlers[what]
+    if not handler then
+      handler={}
+      handlers[what]=handler
+    end
+    return handler
+  end
+  setmetatable(newhandler,{
+    __call=function(t,k) local v=t[k] return v end,
+    __index=function(t,k) local v=setnewhandler(k) t[k]=v return v end,
+  })
+end
+do
+  local newenhancer={}
+  constructors.enhancers=newenhancer
+  constructors.newenhancer=newenhancer
+  local function setnewenhancer(format)
+    local handler=handlers[format]
+    local enhancers=handler.enhancers
+    if not enhancers then
+      local actions=allocate()
+      local before=allocate()
+      local after=allocate()
+      local order=allocate()
+      local patches={ before=before,after=after }
+      local trace=false
+      local report=logs.reporter("fonts",format.." enhancing")
+      trackers.register(format..".loading",function(v) trace=v end)
+      local function enhance(name,data,filename,raw)
+        local enhancer=actions[name]
+        if enhancer then
+          if trace then
+            report("apply enhancement %a to file %a",name,filename)
+            ioflush()
+          end
+          enhancer(data,filename,raw)
+        else
+        end
+      end
+      local function apply(data,filename,raw)
+        local basename=file.basename(lower(filename))
+        if trace then
+          report("%s enhancing file %a","start",filename)
+        end
+        ioflush() 
+        for e=1,#order do
+          local enhancer=order[e]
+          local b=before[enhancer]
+          if b then
+            for pattern,action in next,b do
+              if find(basename,pattern) then
+                action(data,filename,raw)
+              end
+            end
+          end
+          enhance(enhancer,data,filename,raw)
+          local a=after[enhancer]
+          if a then
+            for pattern,action in next,a do
+              if find(basename,pattern) then
+                action(data,filename,raw)
+              end
+            end
+          end
+          ioflush() 
+        end
+        if trace then
+          report("%s enhancing file %a","stop",filename)
+        end
+        ioflush() 
+      end
+      local function register(what,action)
+        if action then
+          if actions[what] then
+          else
+            order[#order+1]=what
+          end
+          actions[what]=action
+        else
+          report("bad enhancer %a",what)
+        end
+      end
+      local function patch(what,where,pattern,action)
+        local pw=patches[what]
+        if pw then
+          local ww=pw[where]
+          if ww then
+            ww[pattern]=action
+          else
+            pw[where]={ [pattern]=action}
+          end
+        end
+      end
+      enhancers={
+        register=register,
+        apply=apply,
+        patch=patch,
+        patches={ register=patch },
+      }
+      handler.enhancers=enhancers
+    end
+    return enhancers
   end
-  return features
+  setmetatable(newenhancer,{
+    __call=function(t,k) local v=t[k] return v end,
+    __index=function(t,k) local v=setnewenhancer(k) t[k]=v return v end,
+  })
 end
-setmetatable(newfeatures,{
-  __call=function(t,k) local v=t[k] return v end,
-  __index=function(t,k) local v=setnewfeatures(k) t[k]=v return v end,
-})
 function constructors.checkedfeatures(what,features)
   local defaults=handlers[what].features.defaults
   if features and next(features) then
@@ -15228,7 +15328,6 @@ if not modules then modules={} end modules ['font-otl']={
 local gmatch,find,match,lower,strip=string.gmatch,string.find,string.match,string.lower,string.strip
 local type,next,tonumber,tostring,unpack=type,next,tonumber,tostring,unpack
 local abs=math.abs
-local ioflush=io.flush
 local derivetable=table.derive
 local formatters=string.formatters
 local setmetatableindex=table.setmetatableindex
@@ -15257,10 +15356,8 @@ local readers=fonts.readers
 local constructors=fonts.constructors
 local otffeatures=constructors.features.otf
 local registerotffeature=otffeatures.register
-local enhancers=allocate()
-otf.enhancers=enhancers
-local patches={}
-enhancers.patches=patches
+local otfenhancers=constructors.enhancers.otf
+local registerotfenhancer=otfenhancers.register
 local forceload=false
 local cleanup=0   
 local syncspace=true
@@ -15276,76 +15373,7 @@ registerdirective("fonts.otf.loader.cleanup",function(v) cleanup=tonumber(v) or
 registerdirective("fonts.otf.loader.force",function(v) forceload=v end)
 registerdirective("fonts.otf.loader.syncspace",function(v) syncspace=v end)
 registerdirective("fonts.otf.loader.forcenotdef",function(v) forcenotdef=v end)
-local ordered_enhancers={
-  "check extra features",
-}
-local actions=allocate()
-local before=allocate()
-local after=allocate()
-patches.before=before
-patches.after=after
-local function enhance(name,data,filename,raw)
-  local enhancer=actions[name]
-  if enhancer then
-    if trace_loading then
-      report_otf("apply enhancement %a to file %a",name,filename)
-      ioflush()
-    end
-    enhancer(data,filename,raw)
-  else
-  end
-end
-function enhancers.apply(data,filename,raw)
-  local basename=file.basename(lower(filename))
-  if trace_loading then
-    report_otf("%s enhancing file %a","start",filename)
-  end
-  ioflush() 
-  for e=1,#ordered_enhancers do
-    local enhancer=ordered_enhancers[e]
-    local b=before[enhancer]
-    if b then
-      for pattern,action in next,b do
-        if find(basename,pattern) then
-          action(data,filename,raw)
-        end
-      end
-    end
-    enhance(enhancer,data,filename,raw)
-    local a=after[enhancer]
-    if a then
-      for pattern,action in next,a do
-        if find(basename,pattern) then
-          action(data,filename,raw)
-        end
-      end
-    end
-    ioflush() 
-  end
-  if trace_loading then
-    report_otf("%s enhancing file %a","stop",filename)
-  end
-  ioflush() 
-end
-function patches.register(what,where,pattern,action)
-  local pw=patches[what]
-  if pw then
-    local ww=pw[where]
-    if ww then
-      ww[pattern]=action
-    else
-      pw[where]={ [pattern]=action}
-    end
-  end
-end
-function patches.report(fmt,...)
-  if trace_loading then
-    report_otf("patching: %s",formatters[fmt](...))
-  end
-end
-function enhancers.register(what,action) 
-  actions[what]=action
-end
+registerotfenhancer("check extra features",function() end) 
 function otf.load(filename,sub,featurefile)
   local featurefile=nil
   local base=file.basename(file.removesuffix(filename))
@@ -15445,7 +15473,7 @@ function otf.load(filename,sub,featurefile)
     otfreaders.unpack(data)
     otfreaders.expand(data) 
     otfreaders.addunicodetable(data)
-    enhancers.apply(data,filename,data)
+    otfenhancers.apply(data,filename,data)
     if applyruntimefixes then
       applyruntimefixes(filename,data)
     end
@@ -18165,6 +18193,12 @@ local getthreshold=injections.getthreshold
 local checkstep=(nodes and nodes.tracers and nodes.tracers.steppers.check)  or function() end
 local registerstep=(nodes and nodes.tracers and nodes.tracers.steppers.register) or function() end
 local registermessage=(nodes and nodes.tracers and nodes.tracers.steppers.message) or function() end
+local function checkdisccontent(d)
+  local pre,post,replace=getdisc(d)
+  if pre   then for n in traverse_id(glue_code,pre)   do print("pre",nodes.idstostring(pre))   break end end
+  if post  then for n in traverse_id(glue_code,post)  do print("pos",nodes.idstostring(post))  break end end
+  if replace then for n in traverse_id(glue_code,replace) do print("rep",nodes.idstostring(replace)) break end end
+end
 local function logprocess(...)
   if trace_steps then
     registermessage(...)
@@ -18225,7 +18259,7 @@ end
 local function copy_glyph(g) 
   local components=getfield(g,"components")
   if components then
-    setfield(g,"components",nil)
+    setfield(g,"components")
     local n=copy_node(g)
     copyinjection(n,g) 
     setfield(g,"components",components)
@@ -18237,11 +18271,18 @@ local function copy_glyph(g)
   end
 end
 local function flattendisk(head,disc)
-  local _,_,replace,_,_,replacetail=getdisc(disc,true)
-  setfield(disc,"replace",nil)
+  local pre,post,replace,pretail,posttail,replacetail=getdisc(disc,true)
+  local prev,next=getboth(disc)
+  local ishead=head==disc
+  setdisc(disc)
   flush_node(disc)
-  if head==disc then
-    local next=getnext(disc)
+  if pre then
+    flush_node_list(pre)
+  end
+  if post then
+    flush_node_list(post)
+  end
+  if ishead then
     if replace then
       if next then
         setlink(replacetail,next)
@@ -18253,7 +18294,6 @@ local function flattendisk(head,disc)
       return 
     end
   else
-    local prev,next=getboth(disc)
     if replace then
       if next then
         setlink(replacetail,next)
@@ -18288,8 +18328,8 @@ local function markstoligature(head,start,stop,char)
   else
     local prev=getprev(start)
     local next=getnext(stop)
-    setprev(start,nil)
-    setnext(stop,nil)
+    setprev(start)
+    setnext(stop)
     local base=copy_glyph(start)
     if head==start then
       head=base
@@ -18336,8 +18376,8 @@ local function toligature(head,start,stop,char,dataset,sequence,markflag,discfou
   local prev=getprev(start)
   local next=getnext(stop)
   local comp=start
-  setprev(start,nil)
-  setnext(stop,nil)
+  setprev(start)
+  setnext(stop)
   local base=copy_glyph(start)
   if start==head then
     head=base
@@ -18401,36 +18441,36 @@ local function toligature(head,start,stop,char,dataset,sequence,markflag,discfou
       local pre,post,replace,pretail,posttail,replacetail=getdisc(discfound,true)
       if not replace then 
         local prev=getprev(base)
-local current=comp
-local previous=nil
-local copied=nil
-while current do
-  if getid(current)==glyph_code then
-    local n=copy_node(current)
-    if copied then
-      setlink(previous,n)
-    else
-      copied=n
-    end
-    previous=n
-  end
-  current=getnext(current)
-end
-        setprev(discnext,nil) 
-        setnext(discprev,nil) 
+        local current=comp
+        local previous=nil
+        local copied=nil
+        while current do
+          if getid(current)==glyph_code then
+            local n=copy_node(current)
+            if copied then
+              setlink(previous,n)
+            else
+              copied=n
+            end
+            previous=n
+          end
+          current=getnext(current)
+        end
+        setprev(discnext) 
+        setnext(discprev) 
         if pre then
           setlink(discprev,pre)
         end
         pre=comp
         if post then
           setlink(posttail,discnext)
-          setprev(post,nil)
+          setprev(post)
         else
           post=discnext
         end
         setlink(prev,discfound)
         setlink(discfound,next)
-        setboth(base,nil,nil)
+        setboth(base)
         setfield(base,"components",copied)
         setdisc(discfound,pre,post,base,discretionary_code)
         base=prev 
@@ -19434,6 +19474,39 @@ end
 local function show_skip(dataset,sequence,char,ck,class)
   logwarning("%s: skipping char %s, class %a, rule %a, lookuptype %a",cref(dataset,sequence),gref(char),class,ck[1],ck[8] or ck[2])
 end
+local new_kern=nuts.pool.kern
+local function checked(head)
+  local current=head
+  while current do
+    if getid(current)==glue_code then
+      local kern=new_kern(getfield(current,"width"))
+      if head==current then
+        local next=getnext(current)
+        if next then
+          setlink(kern,next)
+        end
+        flush_node(current)
+        head=kern
+        current=next
+      else
+        local prev,next=getboth(current)
+        setlink(prev,kern)
+        setlink(kern,next)
+        flush_node(current)
+        current=next
+      end
+    else
+      current=getnext(current)
+    end
+  end
+  return head
+end
+local function setdiscchecked(d,pre,post,replace)
+  if pre   then pre=checked(pre)   end
+  if post  then post=checked(post)  end
+  if replace then replace=checked(replace) end
+  setdisc(d,pre,post,replace)
+end
 local function chaindisk(head,start,last,dataset,sequence,chainlookup,rlmode,k,ck,chainproc)
   if not start then
     return head,start,false
@@ -19454,6 +19527,7 @@ local function chaindisk(head,start,last,dataset,sequence,chainlookup,rlmode,k,c
   local current=start
   local last=start
   local prev=getprev(start)
+  local hasglue=false
   local i=f
   while i<=l do
     local id=getid(current)
@@ -19461,6 +19535,11 @@ local function chaindisk(head,start,last,dataset,sequence,chainlookup,rlmode,k,c
       i=i+1
       last=current
       current=getnext(current)
+    elseif id==glue_code then
+      i=i+1
+      last=current
+      current=getnext(current)
+      hasglue=true
     elseif id==disc_code then
       if keepdisc then
         keepdisc=false
@@ -19510,8 +19589,8 @@ local function chaindisk(head,start,last,dataset,sequence,chainlookup,rlmode,k,c
         tail=find_node_tail(head)
       end
       setnext(sweepnode,current)
-      setprev(head,nil)
-      setnext(tail,nil)
+      setprev(head)
+      setnext(tail)
       appenddisc(sweepnode,head)
     end
   end
@@ -19523,6 +19602,10 @@ local function chaindisk(head,start,last,dataset,sequence,chainlookup,rlmode,k,c
       if id==glyph_code then
         i=i+1
         current=getnext(current)
+      elseif id==glue_code then
+        i=i+1
+        current=getnext(current)
+        hasglue=true
       elseif id==disc_code then
         if keepdisc then
           keepdisc=false
@@ -19564,6 +19647,9 @@ local function chaindisk(head,start,last,dataset,sequence,chainlookup,rlmode,k,c
       local id=getid(current)
       if id==glyph_code then
         i=i-1
+      elseif id==glue_code then
+        i=i-1
+        hasglue=true
       elseif id==disc_code then
         if keepdisc then
           keepdisc=false
@@ -19608,8 +19694,8 @@ local function chaindisk(head,start,last,dataset,sequence,chainlookup,rlmode,k,c
     if cprev then
       setnext(cprev,lookaheaddisc)
     end
-    setprev(cf,nil)
-    setnext(cl,nil)
+    setprev(cf)
+    setnext(cl)
     if startishead then
       head=lookaheaddisc
     end
@@ -19636,7 +19722,11 @@ local function chaindisk(head,start,last,dataset,sequence,chainlookup,rlmode,k,c
       local tail=find_node_tail(new)
       setlink(tail,replace)
     end
-    setdisc(lookaheaddisc,cf,post,new)
+    if hasglue then
+      setdiscchecked(lookaheaddisc,cf,post,new)
+    else
+      setdisc(lookaheaddisc,cf,post,new)
+    end
     start=getprev(lookaheaddisc)
     sweephead[cf]=getnext(clast)
     sweephead[new]=getnext(last)
@@ -19659,8 +19749,8 @@ local function chaindisk(head,start,last,dataset,sequence,chainlookup,rlmode,k,c
       setprev(cnext,backtrackdisc)
     end
     setnext(backtrackdisc,cnext)
-    setprev(cf,nil)
-    setnext(cl,nil)
+    setprev(cf)
+    setnext(cl)
     local pre,post,replace,pretail,posttail,replacetail=getdisc(backtrackdisc,true)
     local new=copy_node_list(cf)
     local cnew=find_node_tail(new)
@@ -19687,7 +19777,11 @@ local function chaindisk(head,start,last,dataset,sequence,chainlookup,rlmode,k,c
     else
       replace=new
     end
-    setdisc(backtrackdisc,pre,post,replace)
+    if hasglue then
+      setdiscchecked(backtrackdisc,pre,post,replace)
+    else
+      setdisc(backtrackdisc,pre,post,replace)
+    end
     start=getprev(backtrackdisc)
     sweephead[post]=getnext(clast)
     sweephead[replace]=getnext(last)
@@ -20341,7 +20435,7 @@ local function kernrun(disc,k_run,font,attr,...)
       if k_run(posttail,"postinjections",next,font,attr,...) then
         done=true
       end
-      setnext(posttail,nil)
+      setnext(posttail)
       setprev(next,disc)
     end
   end
@@ -20363,7 +20457,7 @@ local function kernrun(disc,k_run,font,attr,...)
       if k_run(replacetail,"replaceinjections",next,font,attr,...) then
         done=true
       end
-      setnext(replacetail,nil)
+      setnext(replacetail)
       setprev(next,disc)
     end
   elseif prev and next then
@@ -20430,7 +20524,7 @@ local function testrun(disc,t_run,c_run,...)
     setlink(replacetail,next)
     local ok,overflow=t_run(replace,next,...)
     if ok and overflow then
-      setfield(disc,"replace",nil)
+      setfield(disc,"replace")
       setlink(prev,replace)
       setboth(disc)
       flush_node_list(disc)
@@ -23653,37 +23747,15 @@ local otfreaders=otf.readers
 local otfenhancers=otf.enhancers
 local afmfeatures=constructors.features.afm
 local registerafmfeature=afmfeatures.register
+local afmenhancers=constructors.enhancers.afm
+local registerafmenhancer=afmenhancers.register
 afm.version=1.512 
-afm.cache=containers.define("fonts","afm",afm.version,true)
+afm.cache=containers.define("fonts","one",afm.version,true)
 afm.autoprefixed=true 
 afm.helpdata={} 
 afm.syncspace=true 
 local overloads=fonts.mappings.overloads
 local applyruntimefixes=fonts.treatments and fonts.treatments.applyfixes
-local enhancers={
-}
-local steps={
-  "unify names",
-  "add ligatures",
-  "add extra kerns",
-  "normalize features",
-  "check extra features",
-  "fix names",
-}
-local function applyenhancers(data,filename)
-  for i=1,#steps do
-    local step=steps[i]
-    local enhancer=enhancers[step]
-    if enhancer then
-      if trace_loading then
-        report_afm("applying enhancer %a",step)
-      end
-      enhancer(data,filename)
-    else
-      report_afm("invalid enhancer %a",step)
-    end
-  end
-end
 function afm.load(filename)
   filename=resolvers.findfile(filename,'afm') or ""
   if filename~="" and not fonts.names.ignoredfile(filename) then
@@ -23706,7 +23778,7 @@ function afm.load(filename)
       report_afm("reading %a",filename)
       data=afm.readers.loadfont(filename,pfbname)
       if data then
-        applyenhancers(data,filename)
+        afmenhancers.apply(data,filename)
         fonts.mappings.addtounicode(data,filename)
         otfreaders.pack(data)
         data.size=size
@@ -23731,7 +23803,7 @@ function afm.load(filename)
   end
 end
 local uparser=fonts.mappings.makenameparser() 
-enhancers["unify names"]=function(data,filename)
+local function enhance_unify_names(data,filename)
   local unicodevector=fonts.encodings.agl.unicodes 
   local unicodes={}
   local names={}
@@ -23783,7 +23855,7 @@ enhancers["unify names"]=function(data,filename)
 end
 local everywhere={ ["*"]={ ["*"]=true } } 
 local noflags={ false,false,false,false }
-enhancers["normalize features"]=function(data)
+local function enhance_normalize_features(data)
   local ligatures=setmetatableindex("table")
   local kerns=setmetatableindex("table")
   local extrakerns=setmetatableindex("table")
@@ -23881,8 +23953,7 @@ enhancers["normalize features"]=function(data)
   data.resources.features=features
   data.resources.sequences=sequences
 end
-enhancers["check extra features"]=otf.enhancers.enhance
-enhancers["fix names"]=function(data)
+local function enhance_fix_names(data)
   for k,v in next,data.descriptions do
     local n=v.name
     local r=overloads[n]
@@ -23921,10 +23992,10 @@ local addthem=function(rawdata,ligatures)
     end
   end
 end
-enhancers["add ligatures"]=function(rawdata)
+local function enhance_add_ligatures(rawdata)
   addthem(rawdata,afm.helpdata.ligatures)
 end
-enhancers["add extra kerns"]=function(rawdata) 
+local function enhance_add_extra_kerns(rawdata) 
   local descriptions=rawdata.descriptions
   local resources=rawdata.resources
   local unicodes=resources.unicodes
@@ -24332,6 +24403,12 @@ function readers.pfb(specification,method)
   swap("specification")
   return readers.afm(specification,method)
 end
+registerafmenhancer("unify names",enhance_unify_names)
+registerafmenhancer("add ligatures",enhance_add_ligatures)
+registerafmenhancer("add extra kerns",enhance_add_extra_kerns)
+registerafmenhancer("normalize features",enhance_normalize_features)
+registerafmenhancer("check extra features",otfenhancers.enhance)
+registerafmenhancer("fix names",enhance_fix_names)
 
 end -- closure
 
@@ -24532,8 +24609,11 @@ tfm.version=1.000
 tfm.maxnestingdepth=5
 tfm.maxnestingsize=65536*1024
 local otf=fonts.handlers.otf
+local otfenhancers=otf.enhancers
 local tfmfeatures=constructors.features.tfm
 local registertfmfeature=tfmfeatures.register
+local tfmenhancers=constructors.enhancers.tfm
+local registertfmenhancer=tfmenhancers.register
 constructors.resolvevirtualtoo=false 
 fonts.formats.tfm="type1" 
 fonts.formats.ofm="type1"
@@ -24545,27 +24625,7 @@ function tfm.setfeatures(tfmdata,features)
     return {} 
   end
 end
-local depth={} 
-local enhancers={}
-local steps={
-  "normalize features",
-  "check extra features"
-}
-enhancers["check extra features"]=otf.enhancers.enhance
-local function applyenhancers(data,filename)
-  for i=1,#steps do
-    local step=steps[i]
-    local enhancer=enhancers[step]
-    if enhancer then
-      if trace_loading then
-        report_tfm("applying enhancer %a",step)
-      end
-      enhancer(data,filename)
-    else
-      report_tfm("invalid enhancer %a",step)
-    end
-  end
-end
+local depth={}
 local function read_from_tfm(specification)
   local filename=specification.filename
   local size=specification.size
@@ -24620,7 +24680,7 @@ local function read_from_tfm(specification)
         tfmdata.descriptions=tfmdata.characters
       end
       otf.readers.addunicodetable(tfmdata)
-      applyenhancers(tfmdata,filename)
+      tfmenhancers.apply(tfmdata,filename)
       constructors.applymanipulators("tfm",tfmdata,features,trace_features,report_tfm)
       otf.readers.unifymissing(tfmdata)
       fonts.mappings.addtounicode(tfmdata,filename)
@@ -24921,7 +24981,7 @@ end
 do
   local everywhere={ ["*"]={ ["*"]=true } } 
   local noflags={ false,false,false,false }
-  enhancers["normalize features"]=function(data)
+  local function enhance_normalize_features(data)
     local ligatures=setmetatableindex("table")
     local kerns=setmetatableindex("table")
     local characters=data.characters
@@ -25003,6 +25063,8 @@ do
     data.resources.sequences=sequences
     data.shared.resources=data.shared.resources or resources
   end
+  registertfmenhancer("normalize features",enhance_normalize_features)
+  registertfmenhancer("check extra features",otfenhancers.enhance)
 end
 registertfmfeature {
   name="mode",