1 files changed, 66 insertions, 0 deletions
diff --git a/generate-show-syntax.sml b/generate-show-syntax.sml
new file mode 100644
index 0000000..7e7e38a
--- /dev/null
+++ b/generate-show-syntax.sml
@@ -0,0 +1,66 @@
+use "Result.sml";
+use "Map.sml";
+use "Syntax.sml";
+use "Parser.sml";
+use "Opts.sml";
+
+val header =
+    "fun intToStringI (_ : string) (i : int) : string = Int.toString i\n"
+  ^ "\n"
+  ^ "fun varToStringI (_ : string) (v : Syntax.var) : string = \"Var \" ^ Int.toString v\n"
+  ^ "\n"
+  ^ "fun stringToStringI (_ : string) (s : string) : string = \"\\\"\" ^ String.toString s ^ \"\\\"\"\n"
+  ^ "\n"
+  ^ "fun optionToString (_ : string -> 'a -> string) (_ : string) NONE : string = \"NONE\"\n"
+  ^ "  | optionToString show indent (SOME x) = \"SOME (\" ^ show indent x ^ \")\"\n"
+  ^ "\n"
+  ^ "fun listToString (_ : string -> 'a -> string) (_ : string) ([] : 'a list) : string = \"[]\"\n"
+  ^ "  | listToString show indent [x] = \"[\" ^ show indent x ^ \"]\"\n"
+  ^ "  | listToString show indent xs =\n"
+  ^ "    let val indent' = indent ^ \"  \" in\n"
+  ^ "    \"[\\n\" ^ indent' ^ String.concatWith (\",\\n\" ^ indent') (map (show indent') xs) ^ \"\\n\" ^ indent ^ \"]\"\n"
+  ^ "    end\n"
+
+fun showTy (Syntax.Tyvar var) : string = var ^ "ToStringI"
+  | showTy (Syntax.Tycon ([ty], con)) = con ^ "ToString (" ^ showTy ty ^ ")"
+  | showTy (Syntax.TyTuple tys) =
+    let val vars = List.tabulate (length tys, fn i => "x" ^ Int.toString i)
+    in
+      "(fn indent => fn (" ^ String.concatWith ", " vars ^ ") => let val indent' = indent ^ \"  \" in \"(\\n\" ^ indent' ^ " ^ String.concatWith " ^ \",\\n\" ^ indent' ^ " (map (fn (var, ty) => showTy ty ^ " indent' " ^ var) (ListPair.zip (vars, tys))) ^ " ^ \"\\n\" ^ indent ^ \")\" end)"
+    end
+  | showTy _ = "(fn _ => fn _ => \"UNHANDLED\")"
+
+val opts = { o = ref "/dev/stdout" }
+val flags =
+  [ ("o", Opts.StringOpt (fn arg => #o opts := arg)) ]
+val filename =
+  case Opts.getOpt flags (CommandLine.arguments ()) of
+    [arg] => arg
+  | _ => raise Fail "usage: showsyntax <filename>"
+val ast =
+  case Parser.parse filename of
+    Result.Left e => raise Fail e
+  | Result.Right x => x
+val (structName, decls) =
+  case ast of
+    Syntax.ELet (Syntax.DStruct str :: _, _) => str
+  | _ => raise Fail "ast has unexpected format (I can't print it sorry)"
+val out = TextIO.openOut (!(#o opts))
+val _ = TextIO.output (out, "(*\n  This file was generated by generate-show-syntax.sml. Do not edit manually.\n  To regenerate, use\n\n    sml generate-show-syntax.sml -o " ^ !(#o opts) ^ " " ^ filename ^ "\n*)\n\n")
+val _ = TextIO.output (out, "structure Show" ^ structName ^ " = struct\n")
+val _ = TextIO.output (out, header)
+val _ = map
+  (fn (i, Syntax.DDatatype (typeName, cases)) => (
+      TextIO.output (out,
+          "\n" ^ (if i = 0 then "fun" else "and") ^ " "
+        ^ String.concatWith "\n  | " (map
+            (fn (caseName, NONE) => typeName ^ "ToStringI (indent : string) (" ^ structName ^ "." ^ caseName ^ " : " ^ structName ^ "." ^ typeName ^ ") : string =\n    \"" ^ caseName ^ "\""
+              | (caseName, SOME ty) => typeName ^ "ToStringI (indent : string) (" ^ structName ^ "." ^ caseName ^ " x : " ^ structName ^ "." ^ typeName ^ ") : string =\n    \"" ^ caseName ^ " \" ^ " ^ showTy ty ^ " indent x")
+            cases)
+        ^ "\n");
+      TextIO.output (out, "and " ^ typeName ^ "ToString (x : " ^ structName ^ "." ^ typeName ^ ") : string = " ^ typeName ^ "ToStringI \"\" x\n")
+    )
+    | _ => ())
+  (ListPair.zip (List.tabulate (length decls, fn i => i), decls))
+val _ = TextIO.output(out, "end\n")
+val _ = OS.Process.exit OS.Process.success