Parser constraint error bugs fixed

2 files changed, 77 insertions, 72 deletions

diff --git a/src/packrat-parsers.adb b/src/packrat-parsers.adb
index 6672dc3..f639195 100644
--- a/src/packrat-parsers.adb
+++ b/src/packrat-parsers.adb
@@ -72,6 +72,33 @@ package body Packrat.Parsers is
 
 
 
+    function Element
+           (Hold : in Elem_Holds.Holder)
+        return Traits.Element_Array is
+    begin
+        if Hold.Is_Empty then
+            return Value : Traits.Element_Array (1 .. 0);
+        else
+            return Hold.Element;
+        end if;
+    end Element;
+
+
+    function Element
+           (Hold : in Tok_Holds.Holder)
+        return Graphs.Finished_Token_Array is
+    begin
+        if Hold.Is_Empty then
+            return Value : Graphs.Finished_Token_Array (1 .. 0);
+        else
+            return Hold.Element;
+        end if;
+    end Element;
+
+
+
+
+
     function To_Key
            (Start : in Positive;
             Func  : access function
@@ -125,7 +152,7 @@ package body Packrat.Parsers is
         end if;
         Result := Actual (Context);
         if Result.Status = Needs_More or Result.Status = Optional_More then
-            Context.Needs_More.Insert (My_Key.Start);
+            Context.Needs_More.Include (My_Key.Start);
         end if;
         if Context.Memotable.Contains (My_Key) then
             Context.Memotable.Replace (My_Key, Result);
@@ -281,10 +308,10 @@ package body Packrat.Parsers is
             Temp := Next (Input, Context, R.Finish + 1);
             Adjust.Clear;
             for N of Temp.Results loop
-                Adjust.Insert
+                Adjust.Include
                    ((Finish => N.Finish,
-                     Value  => Elem_Holds.To_Holder (R.Value.Element & N.Value.Element),
-                     Tokens => Tok_Holds.To_Holder (R.Tokens.Element & N.Tokens.Element)));
+                     Value  => Elem_Holds.To_Holder (Element (R.Value) & Element (N.Value)),
+                     Tokens => Tok_Holds.To_Holder (Element (R.Tokens) & Element (N.Tokens))));
             end loop;
             Temp.Results := Adjust;
             Merge (Salt, Temp);
@@ -366,7 +393,9 @@ package body Packrat.Parsers is
         Index : Positive := 1;
     begin
         for R of Root_Result.Results loop
-            Length := Length + Integer (R.Tokens.Element'Length);
+            if not R.Tokens.Is_Empty then
+                Length := Length + Integer (Element (R.Tokens)'Length);
+            end if;
         end loop;
         if Length = 0 then
             return Graphs.Empty_Graph;
@@ -375,7 +404,7 @@ package body Packrat.Parsers is
             Root_Elems : Graphs.Finished_Token_Array (1 .. Length);
         begin
             for R of Root_Result.Results loop
-                for T of R.Tokens.Element loop
+                for T of Element (R.Tokens) loop
                     Root_Elems (Index) := T;
                     Index := Index + 1;
                 end loop;
@@ -399,12 +428,12 @@ package body Packrat.Parsers is
             Real_Input : Traits.Element_Array :=
                 (if Context.Pass_Forward.Is_Empty
                     then Slide (Input, Context.Current_Position)
-                    else Context.Pass_Forward.Element & Input);
+                    else Element (Context.Pass_Forward) & Input);
             Root_Result : Combinator_Result :=
                 Root (Real_Input, Context, Context.Global_Start);
         begin
             if Root_Result.Status = Failure then
-                raise Parser_Error;
+                raise Parser_Error with -Context.Error_String;
             end if;
             if Input'Length = 0 then
                 Result := Finish_Root (Root_Result, Context);
@@ -434,12 +463,12 @@ package body Packrat.Parsers is
             Real_Input : Traits.Element_Array :=
                 (if Context.Pass_Forward.Is_Empty
                     then Slide (Input, Context.Current_Position)
-                    else Context.Pass_Forward.Element & Input);
+                    else Element (Context.Pass_Forward) & Input);
             Root_Result : Combinator_Result :=
                 Root (Real_Input, Context, Context.Global_Start);
         begin
             if Root_Result.Status /= Success then
-                raise Parser_Error;
+                raise Parser_Error with -Context.Error_String;
             end if;
             return Finish_Root (Root_Result, Context);
         end;
@@ -484,21 +513,24 @@ package body Packrat.Parsers is
             Processed : Result_Sets.Set;
         begin
             if Salt.Status = Failure then
-                raise Parser_Error with Packrat.Errors.Encode
-                   (Traits.Label_Enum'Image (Label), Start);
+                Ada.Strings.Unbounded.Append
+                   (Context.Error_String,
+                    Packrat.Errors.Encode (Traits.Label_Enum'Image (Label), Start));
+            else
+                Context.Error_String := +"";
             end if;
             for R of Salt.Results loop
                 Current :=
-                   (Token  => Traits.Tokens.Create (Label, Start, R.Value.Element),
+                   (Token  => Traits.Tokens.Create (Label, Start, Element (R.Value)),
                     Finish => R.Finish);
                 if Salt.Status = Success then
-                    if R.Tokens.Element'Length > 0 then
-                        Context.Result_So_Far.Connect (Current, R.Tokens.Element);
+                    if not R.Tokens.Is_Empty then
+                        Context.Result_So_Far.Connect (Current, Element (R.Tokens));
                     else
                         Context.Result_So_Far.Include (Current.Token);
                     end if;
                 end if;
-                Processed.Insert
+                Processed.Include
                    ((Finish => R.Finish,
                      Value  => Elem_Holds.Empty_Holder,
                      Tokens => Tok_Holds.To_Holder ((1 => Current))));
@@ -526,11 +558,14 @@ package body Packrat.Parsers is
             Processed : Result_Sets.Set;
         begin
             if Salt.Status = Failure then
-                raise Parser_Error with Packrat.Errors.Encode
-                   (Traits.Label_Enum'Image (Label), Start);
+                Ada.Strings.Unbounded.Append
+                   (Context.Error_String,
+                    Packrat.Errors.Encode (Traits.Label_Enum'Image (Label), Start));
+            else
+                Context.Error_String := +"";
             end if;
             for R of Salt.Results loop
-                Processed.Insert
+                Processed.Include
                    ((Finish => R.Finish,
                      Value  => Elem_Holds.Empty_Holder,
                      Tokens => Tok_Holds.Empty_Holder));
@@ -725,7 +760,7 @@ package body Packrat.Parsers is
                 Adjust.Clear;
                 for R of Temp.Results loop
                     if R.Finish = Input'Last or else not Test (Input (R.Finish + 1)) then
-                        Adjust.Insert (R);
+                        Adjust.Include (R);
                     end if;
                 end loop;
                 Temp.Results.Assign (Adjust);
@@ -787,7 +822,7 @@ package body Packrat.Parsers is
             if Start <= Input'Last and then Test (Input (Start)) then
                 Part.Finish := Start;
                 Part.Value := Elem_Holds.To_Holder (Input (Start .. Start));
-                Salt.Results.Insert (Part);
+                Salt.Results.Include (Part);
                 Salt.Status := Success;
             end if;
             return Salt;
@@ -814,7 +849,7 @@ package body Packrat.Parsers is
             if Start <= Input'Last and then Test (Change (Input (Start))) then
                 Part.Finish := Start;
                 Part.Value := Elem_Holds.To_Holder (Input (Start .. Start));
-                Salt.Results.Insert (Part);
+                Salt.Results.Include (Part);
                 Salt.Status := Success;
             end if;
             return Salt;
@@ -842,7 +877,7 @@ package body Packrat.Parsers is
             if Start <= Input'Last and then Input (Start) = Item then
                 Part.Finish := Start;
                 Part.Value := Elem_Holds.To_Holder (Input (Start .. Start));
-                Salt.Results.Insert (Part);
+                Salt.Results.Include (Part);
                 Salt.Status := Success;
             end if;
             return Salt;
@@ -870,7 +905,7 @@ package body Packrat.Parsers is
             if Start <= Input'Last and then Change (Input (Start)) = Item then
                 Part.Finish := Start;
                 Part.Value := Elem_Holds.To_Holder (Input (Start .. Start));
-                Salt.Results.Insert (Part);
+                Salt.Results.Include (Part);
                 Salt.Status := Success;
             end if;
             return Salt;
@@ -916,7 +951,7 @@ package body Packrat.Parsers is
             return Salt : Combinator_Result do
                 Part.Finish := Start + My_Offset;
                 Part.Value := Elem_Holds.To_Holder (Input (Start .. Start + My_Offset));
-                Salt.Results.Insert (Part);
+                Salt.Results.Include (Part);
                 Salt.Status := (if My_Offset < Items'Length - 1 then Needs_More else Success);
             end return;
         end Actual;
@@ -953,7 +988,7 @@ package body Packrat.Parsers is
             return Salt : Combinator_Result do
                 Part.Finish := Start + My_Offset;
                 Part.Value := Elem_Holds.To_Holder (Input (Start .. Start + My_Offset));
-                Salt.Results.Insert (Part);
+                Salt.Results.Include (Part);
                 Salt.Status := (if My_Offset < Number - 1 then Needs_More else Success);
             end return;
         end Actual;
@@ -986,7 +1021,7 @@ package body Packrat.Parsers is
             return Salt : Combinator_Result do
                 Part.Finish := My_Finish;
                 Part.Value := Elem_Holds.To_Holder (Input (Start .. My_Finish));
-                Salt.Results.Insert (Part);
+                Salt.Results.Include (Part);
                 Salt.Status := (if My_Finish = Input'Last and Context.Allow_Incomplete
                     then Optional_More else Success);
             end return;
@@ -1020,7 +1055,7 @@ package body Packrat.Parsers is
             return Salt : Combinator_Result do
                 Part.Finish := My_Finish;
                 Part.Value := Elem_Holds.To_Holder (Input (Start .. My_Finish));
-                Salt.Results.Insert (Part);
+                Salt.Results.Include (Part);
                 Salt.Status := (if My_Finish = Input'Last and Context.Allow_Incomplete
                     then Optional_More else Success);
             end return;
@@ -1044,7 +1079,7 @@ package body Packrat.Parsers is
         Salt : Combinator_Result;
     begin
         Part.Finish := Start - 1;
-        Salt.Results.Insert (Part);
+        Salt.Results.Include (Part);
         Salt.Status := Success;
         return Salt;
     end Empty;
@@ -1061,7 +1096,7 @@ package body Packrat.Parsers is
     begin
         for R of Salt.Results loop
             if R.Finish >= Start then
-                Adjust.Insert (R);
+                Adjust.Include (R);
             end if;
         end loop;
         Salt.Results.Assign (Adjust);
diff --git a/src/packrat-parsers.ads b/src/packrat-parsers.ads
index 93ad258..99dbee7 100644
--- a/src/packrat-parsers.ads
+++ b/src/packrat-parsers.ads
@@ -7,6 +7,7 @@ with
 
 private with
 
+    Ada.Strings.Unbounded,
     Ada.Containers.Vectors,
     Ada.Containers.Ordered_Maps,
     Ada.Containers.Ordered_Sets,
@@ -21,28 +22,6 @@ generic
 package Packrat.Parsers is
 
 
-    --  Memoize only adds to the Parse_Graph result when it is successful
-    --  so the Parser_Context will need to keep track of unsuccessful combinator
-    --  at given positions
-
-    --  If all combinators are memoized in a memotable then no need to keep track of call stack
-    --  To do that, use start point and function access as the key?
-
-    --  If a combinator at a position is already in the memotable, return result
-    --  Else run combinator, add/update result in memotable, then return result
-    --  As a side effect of this, the entry in the memotable will be updated several times
-    --  while left recursion unwinds
-
-    --  Combinators need to return value strings as well as the finish sets
-
-    --  Two functions, Symbolize and Ignore?, to create a node in the graph and to discard
-    --  the current return value string
-
-    --  Some way to join tokens-of-tokens into just tokens
-
-
-
-
     type Parser_Context is private;
 
     Empty_Context : constant Parser_Context;
@@ -315,17 +294,6 @@ private
     --  does the lexer handle input that doesn't start from 1 at the beginning?
 
 
-    --  results need to record what combinators were curtailed, if any, with leftrec count
-
-    --  choice combinators can be curtailed by multiple combinators at once
-
-    --  results need to deal with tokens to put in the graph somehow
-
-
-    --  Curtail when leftrec count exceeds number of remaining tokens plus 1
-    --  for a given combinator/position
-
-
     package Elem_Holds is new Ada.Containers.Indefinite_Holders
        (Element_Type => Traits.Element_Array,
         "="          => Traits."=");
@@ -342,6 +310,14 @@ private
            (Left, Right : in Tok_Holds.Holder)
         return Boolean;
 
+    function Element
+           (Hold : in Elem_Holds.Holder)
+        return Traits.Element_Array;
+
+    function Element
+           (Hold : in Tok_Holds.Holder)
+        return Graphs.Finished_Token_Array;
+
 
 
 
@@ -399,15 +375,6 @@ private
 
 
 
-    --  If there's anything in the Curtails, then Results should be empty
-    --  and vice versa... union?
-
-    --  need to add a record of the total length of input available when
-    --  result was computed, to allow for knowing when to recompute
-    --  optional_more/need_more results
-
-    --  actually no, just not putting optional/needmore results in the
-    --  memotable will work fine, but how to figure out how much to pass forward?
     type Combinator_Result is record
         Results  : Result_Sets.Set := Result_Sets.Empty_Set;
         Curtails : Curtail_Maps.Map := Curtail_Maps.Empty_Map;
@@ -443,6 +410,7 @@ private
         Current_Position : Positive := 1;
         Needs_More       : Needs_Sets.Set;
         Pass_Forward     : Elem_Holds.Holder;
+        Error_String     : Ada.Strings.Unbounded.Unbounded_String;
         Memotable        : Memotables.Map;
         Leftrectable     : Leftrectables.Map;
         Allow_Incomplete : Boolean := True;
@@ -455,6 +423,7 @@ private
         Current_Position => 1,
         Needs_More       => Needs_Sets.Empty_Set,
         Pass_Forward     => Elem_Holds.Empty_Holder,
+        Error_String     => +"",
         Memotable        => Memotables.Empty_Map,
         Leftrectable     => Leftrectables.Empty_Map,
         Allow_Incomplete => True);
@@ -547,6 +516,7 @@ private
 
 
 
+    --  Should this be factored out into the main Packrat package?
     function Slide
            (Input    : in Traits.Element_Array;
             Position : in Positive)