Changeset 148

Timestamp:

Jan 17, 2018, 5:27:23 PM (6 years ago)

Author:

chronos

Message:

• Added: Unfinished support for variable arrays.

Location:

branches/easy compiler

Files:

• UCompiler.pas (modified) (11 diffs)
• UFormMain.pas (modified) (5 diffs)
• USourceCode.pas (modified) (9 diffs)
• USourceExecutor.pas (modified) (6 diffs)
• USourceGenerator.pas (modified) (3 diffs)

branches/easy compiler/UCompiler.pas

@@ -9 +9 @@
 
 type
-  TSourceTokenKind = (stNone, stString, stIdentifier, stEof, stInteger);
+  TSourceTokenKind = (stNone, stString, stIdentifier, stEof, stInteger,
+    stSpecialSymbol);
   TSourceToken = record
     Text: string;
@@ -49 +50 @@
       ): Boolean;
     function ParseFunctionCall(SourceCode: TSourceCode; out FunctionCall: TCommandFunctionCall): Boolean;
-    function ParseIfZero(SourceCode: TSourceCode; out IfZero: TCommandIfZero): Boolean;
+    function ParseIfEqual(SourceCode: TSourceCode; out IfZero: TCommandIfEqual): Boolean;
     function ParseReference(SourceCode: TSourceCode): TSourceReference;
     function ParseReferenceVariable(SourceCode: TSourceCode): TSourceReference;
@@ -126 +127 @@
 procedure TTokenizer.Tokenize(Text: string; Tokens: TSourceTokens);
 type
-  TTokenizerState = (tsNone, tsIdentifier, tsString, tsInteger);
+  TTokenizerState = (tsNone, tsIdentifier, tsString, tsInteger, tsSpecialSymbol);
 var
   State: TTokenizerState;
@@ -153 +154 @@
         Token := '';
       end else
-      raise Exception.Create('Unexpected character');
+      if (Text[I] = '[') or (Text[I] = ']') then begin
+        Tokens.AddToken(stSpecialSymbol, Text[I]);
+      end else
+      raise Exception.Create('Unexpected character: ' + Text[I]);
     end else
     if State = tsIdentifier then begin
       if IsAlphaNumeric(Text[I]) then begin
         Token := Token + Text[I];
-      end else
-      if IsWhiteSpace(Text[I]) then begin
+      end else begin
         Tokens.AddToken(stIdentifier, Token);
         State := tsNone;
         Dec(I);
-      end else
-      raise Exception.Create('Unexpected character');
+      end;
     end else
     if State = tsInteger then begin
       if IsDigit(Text[I]) then begin
         Token := Token + Text[I];
-      end else
-      if IsWhiteSpace(Text[I]) then begin
+      end else begin
         Tokens.AddToken(stInteger, Token);
         State := tsNone;
         Dec(I);
-      end else
-      raise Exception.Create('Unexpected character');
+      end;
     end else
     if State = tsString then begin
@@ -230 +230 @@
 var
   Token: TSourceToken;
+  Token2: TSourceToken;
   NewReference: TSourceReference;
 begin
@@ -239 +240 @@
   end else
   if Token.Kind = stIdentifier then begin
-    NewReference := TSourceReferenceVariable.Create;
-    TSourceReferenceVariable(NewReference).Variable :=
-      SourceCode.Variables.Search(Token.Text);
-    if TSourceReferenceVariable(NewReference).Variable = nil then
-      raise Exception.Create('Variable not found: ' + Token.Text);
+    if Tokenizer.CheckNext('[', stSpecialSymbol) then begin
+      Token2 := Tokenizer.GetNext;
+      NewReference := TSourceReferenceArray.Create;
+      TSourceReferenceArray(NewReference).ArrayRef := SourceCode.Variables.Search(Token.Text);
+      if TSourceReferenceArray(NewReference).ArrayRef = nil then
+        raise Exception.Create('Variable not found: ' + Token.Text);
+      TSourceReferenceArray(NewReference).Index := ParseReference(SourceCode);
+
+      Token2 := Tokenizer.GetNext;
+      if (Token2.Text <> ']') or (Token2.Kind <> stSpecialSymbol) then
+        raise Exception.Create('Expected ]');
+    end else begin
+      NewReference := TSourceReferenceVariable.Create;
+      TSourceReferenceVariable(NewReference).Variable :=
+        SourceCode.Variables.Search(Token.Text);
+      if TSourceReferenceVariable(NewReference).Variable = nil then
+        raise Exception.Create('Variable not found: ' + Token.Text);
+    end;
   end else
   if Token.Kind = stInteger then begin
@@ -257 +271 @@
 var
   Token: TSourceToken;
+  Token2: TSourceToken;
   NewReference: TSourceReference;
 begin
   Token := Tokenizer.GetNext;
   if Token.Kind = stIdentifier then begin
-    NewReference := TSourceReferenceVariable.Create;
-    TSourceReferenceVariable(NewReference).Variable :=
-      SourceCode.Variables.Search(Token.Text);
-    if TSourceReferenceVariable(NewReference).Variable = nil then
-      raise Exception.Create('Variable not found: ' + Token.Text);
-
+    if Tokenizer.CheckNext('[', stSpecialSymbol) then begin
+      Token2 := Tokenizer.GetNext;
+      NewReference := TSourceReferenceArray.Create;
+      TSourceReferenceArray(NewReference).ArrayRef := SourceCode.Variables.Search(Token.Text);
+      if TSourceReferenceArray(NewReference).ArrayRef = nil then
+        raise Exception.Create('Variable not found: ' + Token.Text);
+      TSourceReferenceArray(NewReference).Index := ParseReference(SourceCode);
+
+      Token2 := Tokenizer.GetNext;
+      if (Token2.Text <> ']') or (Token2.Kind <> stSpecialSymbol) then
+        raise Exception.Create('Expected ]');
+    end else begin
+      NewReference := TSourceReferenceVariable.Create;
+      TSourceReferenceVariable(NewReference).Variable :=
+        SourceCode.Variables.Search(Token.Text);
+      if TSourceReferenceVariable(NewReference).Variable = nil then
+        raise Exception.Create('Variable not found: ' + Token.Text);
+    end;
   end else raise Exception.Create('Unexpected parameter');
   Result := NewReference;
@@ -300 +327 @@
 end;
 
-function TCompiler.ParseIfZero(SourceCode: TSourceCode; out IfZero: TCommandIfZero): Boolean;
+function TCompiler.ParseIfEqual(SourceCode: TSourceCode; out IfZero: TCommandIfEqual): Boolean;
 var
   Token: TSourceToken;
@@ -310 +337 @@
   Token := Tokenizer.GetNext;
   Keyword := LowerCase(Token.Text);
-  if Keyword = 'ifzero' then begin
-    IfZero := TCommandIfZero.Create;
-    IfZero.Variable := TSourceReferenceVariable(ParseReferenceVariable(SourceCode));
+  if Keyword = 'ifequal' then begin
+    IfZero := TCommandIfEqual.Create;
+    IfZero.Reference1 := ParseReference(SourceCode);
+    IfZero.Reference2 := ParseReference(SourceCode);
     Result := True;
   end;
@@ -362 +390 @@
 var
   CommandBeginEnd: TCommandBeginEnd;
-  CommandIfZero: TCommandIfZero;
+  CommandIfZero: TCommandIfEqual;
   CommandFunctionCall: TCommandFunctionCall;
   CommandBreak: TCommandBreak;
@@ -373 +401 @@
     Command := CommandBeginEnd;
   end else
-  if ParseIfZero(SourceCode, CommandIfZero) then begin
+  if ParseIfEqual(SourceCode, CommandIfZero) then begin
     Command := CommandIfZero;
   end else

branches/easy compiler/UFormMain.pas

@@ -51 +51 @@
 procedure TForm1.FormShow(Sender: TObject);
 begin
-  with MemoSource.Lines do begin
+{  with MemoSource.Lines do begin
     Add('Begin');
     Add('var I Integer');
@@ -59 +59 @@
     Add('PrintLn I');
     Add('Decrement I 1');
-    Add('IfZero I');
+    Add('IfEqual I 0');
     Add('Break');
     Add('End');
     Add('End');
   end;
-{  with MemoSource.Lines do begin
+  with MemoSource.Lines do begin
     Add('PrintLn ''Super Calculator''');
     Add('var Value1 Integer');
@@ -103 +103 @@
     Add('PrintLn Text3');
   end;
-
+}
   with MemoSource.Lines do begin
+    Add('Begin');
+    Add('Var AnimalName StringArray');
+    Add('Var AnimalProperty StringArray');
+    Add('Var AnimalCount Integer');
+    Add('Var Answer String');
+    Add('Var I Integer');
     Add('Assign AnimalName[0] ''an elephant''');
     Add('Assign AnimalProperty[0] ''It is big and slow''');
@@ -122 +128 @@
         Add('IfEqual Answer ''y''');
         Add('Begin');
-          Add('PrintLn ''That''s clear. It is ''');
+          Add('PrintLn ''Thats clear. It is ''');
           Add('PrintLn AnimalName[I]');
           Add('Break');
         Add('End');
-        Add('Increment I');
-        Add('IfHigherOrEqual I AnimalCount');
+        Add('Increment I 1');
+        Add('IfEqual I AnimalCount');
         Add('Break');
       Add('End');
@@ -138 +144 @@
       Add('PrintLn ''''');
     Add('End');
-  end;
-  }
+    Add('End');
+  end;
+
 end;
 

branches/easy compiler/USourceCode.pas

@@ -28 +28 @@
   end;
 
+  TSourceValues = class(TObjectList)
+  end;
+
   TSourceValueClass = class of TSourceValue;
 
@@ -34 +37 @@
   TSourceType = class
     Name: string;
-    ValueClass: TSourceValueClass;
-  end;
+    function GetValueType: TSourceValueClass; virtual;
+  end;
+
+  TSourceTypeClass = class of TSourceType;
 
   { TSourceTypes }
@@ -41 +46 @@
   TSourceTypes = class(TObjectList)
     Parent: TSourceTypes;
-    function AddNew(Name: string; ClassType: TSourceValueClass): TSourceType;
+    function AddNew(Name: string; ClassType: TSourceTypeClass): TSourceType;
     function Search(Name: string): TSourceType;
   end;
+
+  { TSourceTypeInteger }
+
+  TSourceTypeInteger = class(TSourceType)
+    function GetValueType: TSourceValueClass; override;
+  end;
+
+  { TSourceTypeString }
+
+  TSourceTypeString = class(TSourceType)
+    function GetValueType: TSourceValueClass; override;
+  end;
+
+  { TSourceTypeArray }
+
+  TSourceTypeArray = class(TSourceType)
+    ItemType: TSourceType;
+    function GetValueType: TSourceValueClass; override;
+  end;
+
 
   { TSourceVariable }
@@ -64 +89 @@
   end;
 
+  TSourceReferenceArray = class(TSourceReference)
+    ArrayRef: TSourceVariable;
+    Index: TSourceReference;
+  end;
+
   { TSourceValueString }
 
@@ -76 +106 @@
     Value: Integer;
     procedure Assign(Source: TSourceValue); override;
+  end;
+
+  { TSourceValueArray }
+
+  TSourceValueArray = class(TSourceValue)
+    Items: TSourceValues;
+    procedure Assign(Source: TSourceValue); override;
+    constructor Create;
+    destructor Destroy; override;
   end;
 
@@ -146 +185 @@
   end;
 
-  { TCommandIfZero }
-
-  TCommandIfZero = class(TSourceCommand)
-    Variable: TSourceReferenceVariable;
+  { TCommandIfEqual }
+
+  TCommandIfEqual = class(TSourceCommand)
+    Reference1: TSourceReference;
+    Reference2: TSourceReference;
     destructor Destroy; override;
   end;
@@ -184 +224 @@
 implementation
 
-{ TCommandIfZero }
-
-destructor TCommandIfZero.Destroy;
-begin
-  Variable.Free;
+{ TSourceType }
+
+function TSourceType.GetValueType: TSourceValueClass;
+begin
+  Result := nil;
+end;
+
+{ TSourceTypeInteger }
+
+function TSourceTypeInteger.GetValueType: TSourceValueClass;
+begin
+  Result := TSourceValueInteger;
+end;
+
+{ TSourceTypeString }
+
+function TSourceTypeString.GetValueType: TSourceValueClass;
+begin
+  Result := TSourceValueString;
+end;
+
+{ TSourceTypeArray }
+
+function TSourceTypeArray.GetValueType: TSourceValueClass;
+begin
+  Result := TSourceValueArray;
+end;
+
+{ TSourceValueArray }
+
+procedure TSourceValueArray.Assign(Source: TSourceValue);
+var
+  I: Integer;
+  Value: TSourceValue;
+begin
+  if Source is TSourceValueInteger then begin
+    while Items.Count < TSourceValueArray(Source).Items.Count do begin
+      Value := TSourceValue(TSourceValue(TSourceValueArray(Source).Items[Items.Count]).ClassType.Create);
+      Items.Add(Value);
+    end;
+    while Items.Count > TSourceValueArray(Source).Items.Count do begin
+      Items.Delete(Items.Count - 1);
+    end;
+    for I := 0 to Items.Count - 1 do
+      TSourceValue(Items[I]).Assign(TSourceValue(TSourceValueArray(Source).Items[I]));
+  end else raise Exception.Create('Type for assignment not matches');
+end;
+
+constructor TSourceValueArray.Create;
+begin
+  Items := TSourceValues.Create;
+end;
+
+destructor TSourceValueArray.Destroy;
+begin
+  Items.Free;
+  inherited Destroy;
+end;
+
+{ TCommandIfEqual }
+
+destructor TCommandIfEqual.Destroy;
+begin
+  Reference1.Free;
+  Reference2.Free;
   inherited Destroy;
 end;
@@ -236 +336 @@
 { TSourceTypes }
 
-function TSourceTypes.AddNew(Name: string; ClassType: TSourceValueClass): TSourceType;
-begin
-  Result := TSourceType.Create;
+function TSourceTypes.AddNew(Name: string; ClassType: TSourceTypeClass): TSourceType;
+begin
+  Result := ClassType.Create;
   Result.Name := Name;
-  Result.ValueClass := ClassType;
   Add(Result);
 end;
@@ -395 +494 @@
 var
   Funct: TSourceFunction;
+  Typ: TSourceType;
 begin
   Functions.Clear;
 
   // Init types
-  Types.AddNew('Integer', TSourceValueInteger);
-  Types.AddNew('String', TSourceValueString);
+  Types.AddNew('Integer', TSourceTypeInteger);
+  Types.AddNew('String', TSourceTypeString);
+  Typ := Types.AddNew('StringArray', TSourceTypeArray);
+  TSourceTypeArray(Typ).ItemType := TSourceTypeString.Create;
+  Typ := Types.AddNew('IntegerArray', TSourceTypeArray);
+  TSourceTypeArray(Typ).ItemType := TSourceTypeInteger.Create;
 
   // Init functions

branches/easy compiler/USourceExecutor.pas

@@ -44 +44 @@
     RepeatBlocks: TExecutorRepeats;
     SkipNext: Boolean;
+    procedure ExecuteAssign(CommandAssign: TCommandFunctionCall);
     procedure ExecuteBeginEnd(BeginEnd: TCommandBeginEnd);
     procedure ExecuteCommand(Command: TSourceCommand);
     procedure ExecuteBreak(CommandBreak: TCommandBreak);
+    procedure ExecuteIfEqual(IfEqual: TCommandIfEqual);
     procedure ExecuteRepeat(CommandRepeat: TCommandRepeat);
     function ReadValueReference(Reference: TSourceReference): TSourceValue;
@@ -120 +122 @@
 
 function TSourceExecutor.ReadValueReference(Reference: TSourceReference): TSourceValue;
+var
+  ArrayIndex: TSourceValue;
 begin
   Result := nil;
@@ -127 +131 @@
   if Reference is TSourceReferenceVariable then begin
     Result := Variables.Search(TSourceReferenceVariable(Reference).Variable).Value;
-  end else raise Exception.Create('Unsupported reference');
+  end else
+  if Reference is TSourceReferenceArray then begin
+    ArrayIndex := ReadValueReference(TSourceReferenceArray(Reference).Index);
+    if not (ArrayIndex is TSourceValueInteger) then
+      raise Exception.Create('Only integer array index supported');
+    Result := TSourceValue(TSourceValueArray(Variables.Search(TSourceReferenceArray(Reference).ArrayRef).Value).Items[TSourceValueInteger(ArrayIndex).Value]);
+  end else
+  raise Exception.Create('Unsupported reference');
 end;
 
 function TSourceExecutor.ReadVarReference(Reference: TSourceReference): TSourceVariable;
+var
+  ArrayIndex: TSourceValue;
 begin
   Result := nil;
   if Reference is TSourceReferenceVariable then begin
     Result := TSourceReferenceVariable(Reference).Variable;
+  end else
+  if Reference is TSourceReferenceArray then begin
+    ArrayIndex := ReadValueReference(TSourceReferenceArray(Reference).Index);
+    if not (ArrayIndex is TSourceValueInteger) then
+      raise Exception.Create('Only integer array index supported');
+//    Result := TSourceValue(TSourceValueArray(Variables.Search(TSourceReferenceArray(Reference).ArrayRef).Value).Items[TSourceValueInteger(ArrayIndex)]);
+//TODO:    Result := Variables.Search(TSourceReferenceArray(Reference).ArrayRef);
   end else raise Exception.Create('Unsupported reference');
+end;
+
+procedure TSourceExecutor.ExecuteAssign(CommandAssign: TCommandFunctionCall);
+var
+  Variable: TSourceVariable;
+  Value: TSourceValue;
+  ExecutorVar: TExecutorVariable;
+begin
+  with TCommandFunctionCall(CommandAssign) do begin
+    Variable := ReadVarReference(TSourceReference(Parameters[0]));
+    Value := ReadValueReference(TSourceReference(Parameters[1]));
+    ExecutorVar := Variables.Search(Variable);
+    if not Assigned(ExecutorVar) then begin
+      ExecutorVar := TExecutorVariable.Create;
+      ExecutorVar.Variable := Variable;
+      Variables.Add(ExecutorVar);
+      ExecutorVar.Value := Variable.ValueType.GetValueType.Create;
+    end;
+    ExecutorVar.Value.Assign(Value);
+  end;
 end;
 
@@ -170 +210 @@
   end else
   raise Exception.Create('Used break outside repeat loop');
+end;
+
+procedure TSourceExecutor.ExecuteIfEqual(IfEqual: TCommandIfEqual);
+var
+  Value1: TSourceValue;
+  Value2: TSourceValue;
+begin
+  Value1 := ReadValueReference(IfEqual.Reference1);
+  Value2 := ReadValueReference(IfEqual.Reference2);
+  if (Value1 is TSourceValueInteger) and (Value2 is TSourceValueInteger) then begin
+    if TSourceValueInteger(Value1).Value <> TSourceValueInteger(Value2).Value then
+      SkipNext := True;
+  end else
+  if (Value1 is TSourceValueString) and (Value2 is TSourceValueString) then begin
+    if TSourceValueString(Value1).Value <> TSourceValueString(Value2).Value then
+      SkipNext := True;
+  end else
+  raise Exception.Create('Unsupported types for comparison.');
 end;
 
@@ -235 +293 @@
     end else
     if Name = 'assign' then begin
-      Variable := ReadVarReference(TSourceReference(Parameters[0]));
-      Value := ReadValueReference(TSourceReference(Parameters[1]));
-      ExecutorVar := Variables.Search(Variable);
-      if not Assigned(ExecutorVar) then begin
-        ExecutorVar := TExecutorVariable.Create;
-        ExecutorVar.Variable := Variable;
-        Variables.Add(ExecutorVar);
-        ExecutorVar.Value := Variable.ValueType.ValueClass.Create;
-      end;
-      ExecutorVar.Value.Assign(Value);
+      ExecuteAssign(TCommandFunctionCall(Command));
     end else
     if Name = 'increment' then begin
@@ -272 +321 @@
     ExecuteBreak(TCommandBreak(Command));
   end else
-  if Command is TCommandIfZero then begin
-    ExecutorVar := Variables.Search(TCommandIfZero(Command).Variable.Variable);
-    if Assigned(ExecutorVar) then begin
-      if ExecutorVar.Variable.ValueType.Name = 'Integer' then begin
-        if TSourceValueInteger(ExecutorVar.Value).Value <> 0 then SkipNext := True;
-      end else
-      raise Exception.Create('Can compare only integers');
-    end else
-    raise Exception.Create('Variable not found');
+  if Command is TCommandIfEqual then begin
+    ExecuteIfEqual(TCommandIfEqual(Command));
   end else
   if Command is TCommandRepeat then begin

branches/easy compiler/USourceGenerator.pas

@@ -44 +44 @@
     else if ValueType.Name = 'Integer' then
       Result := Result + 'Integer'
+    else if ValueType.Name = 'StringArray' then
+      Result := Result + 'array of string'
+    else if ValueType.Name = 'IntegerArray' then
+      Result := Result + 'array of Integer'
     else raise Exception.Create('Unsupported type');
     Result := Result + ';' + LineEnding;
@@ -66 +70 @@
   if Reference is TSourceReferenceVariable then begin
     Result := Result + TSourceReferenceVariable(Reference).Variable.Name;
+  end else
+  if Reference is TSourceReferenceArray then begin
+    Result := Result + TSourceReferenceArray(Reference).ArrayRef.Name +
+      '[' + GenerateRef(TSourceReferenceArray(Reference).Index) + ']';
   end else raise Exception.Create('Unsupported parameter type');
 end;
@@ -116 +124 @@
     Result := Result + IndentStr + 'until False;' + LineEnding;
   end else
-  if Command is TCommandIfZero then begin
-    Result := Result + IndentStr + 'if ' + TCommandIfZero(Command).Variable.Variable.Name + ' = 0 then ';
+  if Command is TCommandIfEqual then begin
+    Result := Result + IndentStr + 'if ' + GenerateRef(TCommandIfEqual(Command).Reference1) +
+      ' = ' + GenerateRef(TCommandIfEqual(Command).Reference2) + ' then ';
   end else
   raise Exception.Create('Unsupported instruction');