(* Title: Tools/Code/code_namespace.ML
Author: Florian Haftmann, TU Muenchen
Mastering target language namespaces.
*)
signature CODE_NAMESPACE =
sig
datatype ('a, 'b) node =
Dummy
| Stmt of 'a
| Module of ('b * (string * ('a, 'b) node) Graph.T);
val hierarchical_program: (string -> string) -> { module_alias: string -> string option,
reserved: Name.context, empty_nsp: 'c, namify_module: string -> 'c -> string * 'c,
namify_stmt: Code_Thingol.stmt -> string -> 'c -> string * 'c,
cyclic_modules: bool, empty_data: 'b, memorize_data: string -> 'b -> 'b,
modify_stmt: Code_Thingol.stmt -> Code_Thingol.stmt option }
-> Code_Thingol.program
-> { deresolver: string list -> string -> string,
hierarchical_program: (string * (Code_Thingol.stmt, 'b) node) Graph.T }
end;
structure Code_Namespace : CODE_NAMESPACE =
struct
(* hierarchical program structure *)
datatype ('a, 'b) node =
Dummy
| Stmt of 'a
| Module of ('b * (string * ('a, 'b) node) Graph.T);
fun map_module_content f (Module content) = Module (f content);
fun map_module [] = I
| map_module (name_fragment :: name_fragments) =
apsnd o Graph.map_node name_fragment o apsnd o map_module_content
o map_module name_fragments;
fun hierarchical_program labelled_name { module_alias, reserved, empty_nsp,
namify_module, namify_stmt, cyclic_modules, empty_data, memorize_data, modify_stmt } program =
let
(* building module name hierarchy *)
fun alias_fragments name = case module_alias name
of SOME name' => Long_Name.explode name'
| NONE => map (fn name => fst (yield_singleton Name.variants name reserved))
(Long_Name.explode name);
val module_names = Graph.fold (insert (op =) o fst o Code_Printer.dest_name o fst) program [];
val fragments_tab = fold (fn name => Symtab.update
(name, alias_fragments name)) module_names Symtab.empty;
val dest_name = Code_Printer.dest_name #>> (the o Symtab.lookup fragments_tab);
(* building empty module hierarchy *)
val empty_module = (empty_data, Graph.empty);
fun ensure_module name_fragment (data, nodes) =
if can (Graph.get_node nodes) name_fragment then (data, nodes)
else (data,
nodes |> Graph.new_node (name_fragment, (name_fragment, Module empty_module)));
fun allocate_module [] = I
| allocate_module (name_fragment :: name_fragments) =
ensure_module name_fragment
#> (apsnd o Graph.map_node name_fragment o apsnd o map_module_content o allocate_module) name_fragments;
val empty_program = Symtab.fold (fn (_, fragments) => allocate_module fragments)
fragments_tab empty_module;
(* distribute statements over hierarchy *)
fun add_stmt name stmt =
let
val (name_fragments, base) = dest_name name;
in
(map_module name_fragments o apsnd) (Graph.new_node (name, (base, Stmt stmt)))
end;
fun add_dependency name name' =
let
val (name_fragments, base) = dest_name name;
val (name_fragments', base') = dest_name name';
val (name_fragments_common, (diff, diff')) =
chop_prefix (op =) (name_fragments, name_fragments');
val (is_module, dep) = if null diff then (false, (name, name'))
else (true, (hd diff, hd diff'))
val add_edge = if is_module andalso not cyclic_modules
then (fn node => Graph.add_edge_acyclic dep node
handle Graph.CYCLES _ => error ("Dependency "
^ quote name ^ " -> " ^ quote name'
^ " would result in module dependency cycle"))
else Graph.add_edge dep
in (map_module name_fragments_common o apsnd) add_edge end;
val proto_program = empty_program
|> Graph.fold (fn (name, (stmt, _)) => add_stmt name stmt) program
|> Graph.fold (fn (name, (_, (_, names))) => fold (add_dependency name) names) program;
(* name declarations, data and statement modifications *)
fun make_declarations nsps (data, nodes) =
let
val (module_fragments, stmt_names) = List.partition
(fn name_fragment => case Graph.get_node nodes name_fragment
of (_, Module _) => true | _ => false) (Graph.keys nodes);
fun declare namify name (nsps, nodes) =
let
val (base, node) = Graph.get_node nodes name;
val (base', nsps') = namify node base nsps;
val nodes' = Graph.map_node name (K (base', node)) nodes;
in (nsps', nodes') end;
val (nsps', nodes') = (nsps, nodes)
|> fold (declare (K namify_module)) module_fragments
|> fold (declare (namify_stmt o (fn Stmt stmt => stmt))) stmt_names;
val nodes'' = nodes'
|> fold (fn name_fragment => (Graph.map_node name_fragment
o apsnd o map_module_content) (make_declarations nsps')) module_fragments
|> fold (fn name => (Graph.map_node name o apsnd) (fn Stmt stmt =>
case modify_stmt stmt of NONE => Dummy | SOME stmt => Stmt stmt)) stmt_names;
val data' = fold memorize_data stmt_names data;
in (data', nodes'') end;
val (_, hierarchical_program) = make_declarations empty_nsp proto_program;
(* deresolving *)
fun deresolver prefix_fragments name =
let
val (name_fragments, _) = dest_name name;
val (_, (_, remainder)) = chop_prefix (op =) (prefix_fragments, name_fragments);
val nodes = fold (fn name_fragment => fn nodes => case Graph.get_node nodes name_fragment
of (_, Module (_, nodes)) => nodes) name_fragments hierarchical_program;
val (base', _) = Graph.get_node nodes name;
in Long_Name.implode (remainder @ [base']) end
handle Graph.UNDEF _ => error ("Unknown statement name: " ^ labelled_name name);
in { deresolver = deresolver, hierarchical_program = hierarchical_program } end;
end;