Added [CodeBits.listiflazy].

Replaced a few redundant tests [if Settings.table then ...]
with assertions [assert Settings.table].

src/codeBits.ml

@@ -17,6 +17,12 @@ let elementif condition x =
   else
     []
 
+let listiflazy condition xs =
+  if condition then
+    xs()
+  else
+    []
+
 (* The unit type. *)
 
 let tunit =

src/codeBits.mli

@@ -3,11 +3,17 @@
 
 open IL
 
-(* A list subject to a condition. *)
+(* A list subject to a condition. (Be careful, though: the list is
+   of course constructed even if the condition is false.) *)
 
 val listif: bool -> 'a list -> 'a list
 val elementif: bool -> 'a -> 'a list
 
+(* A lazy version of [listif], where the list is constructed only
+   if the condition is true. *)
+
+val listiflazy: bool -> (unit -> 'a list) -> 'a list
+
 (* Standard types. *)
 
 val tunit: typ

src/interface.ml

@@ -68,7 +68,7 @@ let interface grammar = [
 
     (* The incremental engine and API. *)
 
-    listif Settings.table [
+    listiflazy Settings.table (fun () -> [
       IIComment "The incremental API.";
       IIModule (
         interpreter,
@@ -85,11 +85,11 @@ let interface grammar = [
           (incremental symbol, entrytypescheme_incremental grammar symbol) :: decls
         ) grammar.start_symbols []
       )
-    ] @
+    ]) @
 
     (* The inspection API. *)
 
-    listif Settings.table (
+    listiflazy Settings.table (fun () ->
       TokenType.tokengadtdef grammar @
       NonterminalType.nonterminalgadtdef grammar @
       SymbolType.symbolgadtdef grammar @

src/nonterminalType.ml

@@ -22,37 +22,34 @@ let tnonterminalgadtdata nt =
 exception MissingOCamlType
 
 let nonterminalgadtdef grammar =
-  if Settings.table then
-    try
-      let datadefs =
-        List.fold_left (fun defs nt ->
-          let index =
-            match ocamltype_of_symbol grammar nt with
-            | Some t ->
-                TypTextual t
-            | None ->
-                raise MissingOCamlType
-          in
-          {
-            dataname = tnonterminalgadtdata nt;
-            datavalparams = [];
-            datatypeparams = Some [ index ]
-          } :: defs
-        ) [] (nonterminals grammar)
-      in
-      [
-        IIComment "The indexed type of nonterminal symbols.";
-        IITypeDecls [{
-          typename = tcnonterminalgadt;
-          typeparams = [ "_" ];
-          typerhs = TDefSum datadefs;
-          typeconstraint = None
-        }]
-      ]
-    with MissingOCamlType ->
-      (* If the type of some nonterminal symbol is unknown, give up
-         on the whole thing. *)
-      []
-  else
+  assert Settings.table;
+  try
+    let datadefs =
+      List.fold_left (fun defs nt ->
+        let index =
+          match ocamltype_of_symbol grammar nt with
+          | Some t ->
+              TypTextual t
+          | None ->
+              raise MissingOCamlType
+        in
+        {
+          dataname = tnonterminalgadtdata nt;
+          datavalparams = [];
+          datatypeparams = Some [ index ]
+        } :: defs
+      ) [] (nonterminals grammar)
+    in
+    [
+      IIComment "The indexed type of nonterminal symbols.";
+      IITypeDecls [{
+        typename = tcnonterminalgadt;
+        typeparams = [ "_" ];
+        typerhs = TDefSum datadefs;
+        typeconstraint = None
+      }]
+    ]
+  with MissingOCamlType ->
+    (* If the type of some nonterminal symbol is unknown, give up
+       on the whole thing. *)
     []
-

src/symbolType.ml

@@ -21,6 +21,7 @@ let dataN =
 (* The definition of the symbol GADT. *)
 
 let symbolgadtdef grammar =
+  assert Settings.table;
   (* This definition can be produced only if we are successfully able
      to construct the nonterminal GADT. *)
   match NonterminalType.nonterminalgadtdef grammar with

src/tokenType.ml

@@ -71,37 +71,35 @@ let tokentypedef grammar =
    GADTs. *)
 
 let tokengadtdef grammar =
-  if Settings.table then
-    let datadefs =
-      StringMap.fold (fun token properties defs ->
-        if properties.tk_is_declared then
-          let index =
-            match properties.tk_ocamltype with
-            | None ->
-                tunit
-            | Some t ->
-                TypTextual t
-          in
-          {
-            dataname = ttokengadtdata token;
-            datavalparams = [];
-            datatypeparams = Some [ index ]
-          } :: defs
-        else
-          defs
-      ) grammar.tokens []
-    in
-    [
-      IIComment "The indexed type of terminal symbols.";
-      IITypeDecls [{
-        typename = tctokengadt;
-        typeparams = [ "_" ];
-        typerhs = TDefSum datadefs;
-        typeconstraint = None
-      }]
-    ]
-  else
-    []
+  assert Settings.table;
+  let datadefs =
+    StringMap.fold (fun token properties defs ->
+      if properties.tk_is_declared then
+        let index =
+          match properties.tk_ocamltype with
+          | None ->
+              tunit
+          | Some t ->
+              TypTextual t
+        in
+        {
+          dataname = ttokengadtdata token;
+          datavalparams = [];
+          datatypeparams = Some [ index ]
+        } :: defs
+      else
+        defs
+    ) grammar.tokens []
+  in
+  [
+    IIComment "The indexed type of terminal symbols.";
+    IITypeDecls [{
+      typename = tctokengadt;
+      typeparams = [ "_" ];
+      typerhs = TDefSum datadefs;
+      typeconstraint = None
+    }]
+  ]
 
 (* If we were asked to only produce a type definition, then
    do so and stop. *)
@@ -116,7 +114,9 @@ let produce_tokentypes grammar =
 
       let i =
         tokentypedef grammar @
-        tokengadtdef grammar
+        listiflazy Settings.table (fun () ->
+          tokengadtdef grammar
+        )
       in
 
       let module P =