Changeset 56 for trunk/Compiler/Target/Interpretter/UTargetInterpretter.pas

Timestamp:

Jul 13, 2012, 2:10:18 PM (12 years ago)

Author:

chronos

Message:

• Modified: Slightly enhanced unfinished interpretter.

File:

• trunk/Compiler/Target/Interpretter/UTargetInterpretter.pas (modified) (5 diffs)

trunk/Compiler/Target/Interpretter/UTargetInterpretter.pas

@@ -32 +32 @@
     procedure RunAssignment(Assignment: TAssignment);
     procedure RunCaseOfEnd(CaseOfEnd: TCaseOfEnd);
-    procedure RunFunction(FunctionCall: TFunctionCall);
+    function RunFunction(FunctionCall: TFunctionCall): TValue;
     procedure RunForToDo(ForToDo: TForToDo);
-    function Evaluate(Expression: TExpression): Boolean;
+    function Evaluate(Expression: TExpression): TValue;
   public
     Variables: TListObject;
@@ -50 +50 @@
 resourcestring
   SUnknownCommandType = 'Unknown command type';
+  SUnknownOperator = 'Unknown operator "%s"';
 
 { TExecutorInterpretter }
@@ -94 +95 @@
 procedure TExecutorInterpretter.RunAssignment(Assignment: TAssignment);
 begin
-  //Assignment.Target := Assignment.Source;
+  Assignment.Target.Value := Evaluate(Assignment.Source);
 end;
 
@@ -111 +112 @@
 end;
 
-procedure TExecutorInterpretter.RunFunction(FunctionCall: TFunctionCall);
+function TExecutorInterpretter.RunFunction(FunctionCall: TFunctionCall): TValue;
 begin
   RunBeginEnd(FunctionCall.FunctionRef.Code);
@@ -126 +127 @@
 end;
 
-function TExecutorInterpretter.Evaluate(Expression: TExpression): Boolean;
+function TExecutorInterpretter.Evaluate(Expression: TExpression): TValue;
 begin
-//  case Expression.NodeType of
-//    ntConstant: ;
-//  end;
+  with Expression do
+  case NodeType of
+    ntConstant: Result := Constant.Value;
+    ntFunction: Result := RunFunction(FunctionCall);
+    ntOperator: begin
+      if OperatorName = '>' then
+        Result := Evaluate(TExpression(SubItems.First)) > Evaluate(TExpression(SubItems.Last))
+      else if OperatorName = '<' then
+        Result := Evaluate(TExpression(SubItems.First)) < Evaluate(TExpression(SubItems.Last))
+      else if OperatorName = '+' then
+        Result := Evaluate(TExpression(SubItems.First)) + Evaluate(TExpression(SubItems.Last))
+      else if OperatorName = '-' then
+        Result := Evaluate(TExpression(SubItems.First)) - Evaluate(TExpression(SubItems.Last))
+      else if OperatorName = '*' then
+        Result := Evaluate(TExpression(SubItems.First)) * Evaluate(TExpression(SubItems.Last))
+      else if OperatorName = 'div' then
+        Result := Evaluate(TExpression(SubItems.First)) div Evaluate(TExpression(SubItems.Last))
+        else raise Exception.CreateFmt(SUnknownOperator, [OperatorName]);
+    end;
+    ntVariable: Result := Variable.Value;
+  end;
 end;