Changeset 102 for branches/interpreter/Parser3.pas

Timestamp:

Feb 11, 2017, 6:55:42 PM (8 years ago)

Author:

chronos

Message:

• Modified: Now project3 can interpret project2.
• Modified: To support standard input and output inside interpreter, all lines read from input starting with | symbol is passed to interpreted code. Also text written to standard output by interpretted program is prefixed with | symbol.

File:

• branches/interpreter/Parser3.pas (modified) (7 diffs)

branches/interpreter/Parser3.pas

@@ -10 +10 @@
 procedure ParseProgram(ProgramCode: PProgramCode);
 
+
+var
+  InnerText: string;
+  InnerTextPos: Integer;
 
 implementation
@@ -61 +65 @@
 procedure ReadInputAll;
 var
+  LastC: Char;
   C: Char;
-begin
+  Inner: Boolean;
+begin
+  LastC := #0;
   InputTextPos := 1;
   InputText := '';
+  InnerTextPos := 1;
+  InnerText := '';
+  Inner := False;
   while not Eof do begin
     Read(C);
-    InputText := InputText + C;
+    if ((LastC = #0) or (LastC = #13) or (LastC = #10)) and (C = '|') then begin
+      Inner := True;
+      LastC := C;
+      Continue;
+    end else
+    if ((LastC = #0) or (LastC = #13) or (LastC = #10)) and (C <> '|') then begin
+      Inner := False;
+    end;
+    if Inner then InnerText := InnerText + C
+      else InputText := InputText + C;
+    LastC := C;
   end;
 end;
@@ -296 +316 @@
   I: Integer;
   II: Integer;
-begin
+  FoundOperator: Boolean;
+  OldPos: Integer;
+begin
+  OldPos := InputTextPos;
   Result := True;
+  FoundOperator := False;
   repeat
     if CheckNext('(') then begin
@@ -312 +336 @@
       Expression^.Items[Length(Expression^.Items) - 1].NodeType := ntOperator;
       Expression^.Items[Length(Expression^.Items) - 1].OperatorType := ExpOperator;
+      FoundOperator := True;
     end else
     if ParseGetValue(@GetValue, True) then begin
@@ -322 +347 @@
     end;
   until False;
+  if not FoundOperator then begin
+    Result := False;
+    InputTextPos := OldPos;
+    Exit;
+  end;
 
   if Length(Expression^.Items) > 0 then begin
@@ -340 +370 @@
             Expression^.Items[I].Associated := True;
             SetLength(Expression^.Items[I].Items, 2);
-            Expression^.Items[I].Items[1] := Expression^.Items[I - 1];
-            Expression^.Items[I].Items[0] := Expression^.Items[I + 1];
+            Expression^.Items[I].Items[0] := Expression^.Items[I - 1];
+            Expression^.Items[I].Items[1] := Expression^.Items[I + 1];
             DeleteExpressionItem(Expression, I + 1);
             DeleteExpressionItem(Expression, I - 1);
@@ -686 +716 @@
   ProgramCode^.Functions.Add(FunctionCreate('Read', nil));
   FuncRead := ProgramCode^.Functions.GetLast;
-  FuncRead^.Parameters.Add(FunctionParameterCreate('Output', TypeChar));
+  FuncRead^.Parameters.Add(FunctionParameterCreate('Output', TypeChar, True));
+  FuncRead^.Variables.Add(VariableCreate('Output', TypeChar));
   ProgramCode^.Functions.Add(FunctionCreate('Eof', TypeBoolean));
   ProgramCode^.Functions.Add(FunctionCreate('Length', TypeInteger));