Changeset 125 for branches/generator/URules.pas

Timestamp:

Nov 29, 2017, 6:31:25 PM (7 years ago)

Author:

chronos

Message:

• Added: Generate Parser as separate file.

File:

• branches/generator/URules.pas (modified) (6 diffs)

branches/generator/URules.pas

@@ -111 +111 @@
     FModified: Boolean;
     procedure SetModified(AValue: Boolean);
+    procedure BuildParser(FileName: string);
     procedure BuildMain(FileName: string);
     procedure BuildSource(FileName: string);
@@ -137 +138 @@
 end;
 
-procedure TGrammer.BuildMain(FileName: string);
+procedure TGrammer.BuildParser(FileName: string);
 var
   ParserFile: TStringList;
+  Rule: TRule;
+  I: Integer;
+  Line: string;
+  Item: TRuleItem;
 begin
   ParserFile := TStringList.Create;
   with ParserFile do begin
-    Add('program Compiler;');
+    Add('unit Parse;');
     Add('');
     Add('{$MODE Delphi}');
     Add('');
-    Add('uses');
-    Add('  Source;');
-    Add('');
-    Add('procedure Compile(FileName: string);');
+    Add('interface');
+    Add('');
+    Add('type');
+    Add('  TParser = class');
+    Add('    Content: string;');
+    Add('    Position: Integer;');
+    Add('    function Expect(Text: string; Required: Boolean = False): Boolean;');
+    Add('    function ExpectRange(CharFrom, CharTo: Char; Required: Boolean = False): Boolean;');
+    for Rule in Rules do
+      Add('    function Parse' + Rule.Name + ': Boolean;');
+    Add('  end;');
+    Add('');
+    Add('implementation');
+    Add('');
+    Add('function TParser.Expect(Text: string; Required: Boolean = False): Boolean;');
     Add('var');
-    Add('  SourceFile: Text;');
+    Add('  ReadText: string;');
     Add('begin');
-    Add('  AssignFile(SourceFile, FileName);');
-    Add('  Reset(SourceFile);');
-    Add('  SetLength(Content, FileSize(SourceFile));');
-    Add('  Read(SourceFile, Content);');
-    if Assigned(TopRule) then
-      Add('  Parse' + TopRule.Name + ';');
-    Add('  CloseFile(SourceFile);');
+    Add('  ReadText := Copy(Content, Position, Length(Text));');
+    Add('  Inc(Position, Length(Text));');
+    Add('  Result := Text = ReadText');
+    Add('  if not Result and Required then Error(''Expected '' + Text + '' but found '' + ReadText + ''.'');');
     Add('end;');
     Add('');
+    Add('function TParser.ExpectRange(CharFrom, CharTo: char; Required: Boolean = False): Boolean;');
+    Add('var');
+    Add('  ReadChar: Char;');
     Add('begin');
-    Add('  if ParamCount > 1 then');
-    Add('    Compile(ParamStr(1));');
-    Add('end.');
-    SaveToFile(FileName);
-  end;
-  FreeAndNil(ParserFile);
-end;
-
-procedure TGrammer.BuildSource(FileName: string);
-var
-  Rule: TRule;
-  Item: TRuleItem;
-  Line: string;
-  I: Integer;
-  SourceFile: TStringList;
-begin
-  SourceFile := TStringList.Create;
-  with SourceFile do begin
-    Add('unit Source;');
-    Add('');
-    Add('{$MODE Delphi}');
-    Add('');
-    Add('interface');
-    Add('');
-    Add('uses');
-    Add('  fgl;');
-    Add('');
-    Add('type');
-    for Rule in Rules do
-    if Rule.CreateSourceNode then begin
-      Add('  T' + Rule.Name + ' = class;');
-    end;
-    Add('');
-    for Rule in Rules do
-    if Rule.CreateSourceNode then begin
-      Add('  T' + Rule.Name + ' = class');
-      for Item in Rule.Items do begin
-        if Item.RuleItemType = ritNonTerminal then
-          if Item.Repetitive then
-          Add('    ' + Item.NonTerminal.Name + ': TFPGObjectList<T' + Item.NonTerminal.Name + '>;')
-          else Add('    ' + Item.NonTerminal.Name + ': T' + Item.NonTerminal.Name + ';');
-      end;
-      Add('  end;' + LineEnding);
-    end;
-    Add('');
-    Add('implementation');
+    Add('  ReadChar := Content[Position];');
+    Add('  Inc(Position, 1);');
+    Add('  Result := (ReadChar >= CharFrom) and (ReadChar <= CharTo);');
+    Add('  if not Result and Required then Error(''Expected '' + CharFrom + '' to '' + CharTo + '' but found '' + ReadChar + ''.'');');
+    Add('end;');
     Add('');
     for Rule in Rules do begin
-      Add('function Parse' + Rule.Name + ': Boolean;');
+      Add('function TParser.Parse' + Rule.Name + ': Boolean;');
       Add('begin');
       I := 0;
@@ -225 +200 @@
         end;
         case Item.RuleItemType of
-          ritTerminal: Line := Line + 'Expect(''' + Item.Terminal + ''')';
+          ritTerminal: Line := Line + 'Expect(''' + StringReplace(Item.Terminal, '''', '''''', [rfReplaceAll]) + ''')';
           ritNonTerminal: Line := Line + 'Parse' + Item.NonTerminal.Name;
-          ritTerminalRange: Line := Line + 'Expect(''' + Item.Terminal + ''')';
+          ritTerminalRange: Line := Line + 'ExpectRange(''' + Item.TerminalFrom + ''', ''' + Item.TerminalTo + ''')';
+          //ritSubItems: Line := 'Parse +';
         end;
         if Rule.Items.RuleType = rtOr then begin
@@ -244 +220 @@
       Add('');
     end;
+    Add('');
+    Add('end.');
+    SaveToFile(FileName);
+  end;
+  FreeAndNil(ParserFile);
+end;
+
+procedure TGrammer.BuildMain(FileName: string);
+var
+  ParserFile: TStringList;
+begin
+  ParserFile := TStringList.Create;
+  with ParserFile do begin
+    Add('program Compiler;');
+    Add('');
+    Add('{$MODE Delphi}');
+    Add('');
+    Add('uses');
+    Add('  Source, Parser;');
+    Add('');
+    Add('procedure Compile(FileName: string);');
+    Add('var');
+    Add('  SourceFile: Text;');
+    Add('begin');
+    Add('  AssignFile(SourceFile, FileName);');
+    Add('  Reset(SourceFile);');
+    Add('  SetLength(Content, FileSize(SourceFile));');
+    Add('  Parser := TParser.Create;');
+    Add('  Read(SourceFile, Parser.Content);');
+    Add('  CloseFile(SourceFile);');
+    if Assigned(TopRule) then
+      Add('  Parser.Parse' + TopRule.Name + ';');
+    Add('  Parser.Free;');
+    Add('end;');
+    Add('');
+    Add('begin');
+    Add('  if ParamCount > 1 then');
+    Add('    Compile(ParamStr(1));');
+    Add('end.');
+    SaveToFile(FileName);
+  end;
+  FreeAndNil(ParserFile);
+end;
+
+procedure TGrammer.BuildSource(FileName: string);
+var
+  Rule: TRule;
+  Item: TRuleItem;
+  SourceFile: TStringList;
+begin
+  SourceFile := TStringList.Create;
+  with SourceFile do begin
+    Add('unit Source;');
+    Add('');
+    Add('{$MODE Delphi}');
+    Add('');
+    Add('interface');
+    Add('');
+    Add('uses');
+    Add('  fgl;');
+    Add('');
+    Add('type');
+    for Rule in Rules do
+    if Rule.CreateSourceNode then begin
+      Add('  T' + Rule.Name + ' = class;');
+    end;
+    Add('');
+    for Rule in Rules do
+    if Rule.CreateSourceNode then begin
+      Add('  T' + Rule.Name + ' = class');
+      for Item in Rule.Items do begin
+        if Item.RuleItemType = ritNonTerminal then
+          if Item.Repetitive then
+          Add('    ' + Item.NonTerminal.Name + ': TFPGObjectList<T' + Item.NonTerminal.Name + '>;')
+          else Add('    ' + Item.NonTerminal.Name + ': T' + Item.NonTerminal.Name + ';');
+      end;
+      Add('  end;' + LineEnding);
+    end;
+    Add('');
+    Add('implementation');
+    Add('');
 
     Add('end.');
@@ -258 +315 @@
   RulesNode: TDOMNode;
   Rule: TRule;
-  TopRuleName: string;
 begin
   Self.FileName := FileName;
@@ -329 +385 @@
 
   BuildMain(OutputDir + DirectorySeparator + 'Compiler.pas');
-  BuildSource(OutputDir + DirectorySeparator +'Source.pas');
+  BuildSource(OutputDir + DirectorySeparator + 'Source.pas');
+  BuildParser(OutputDir + DirectorySeparator + 'Parser.pas');
 end;