Ejemplo n.º 1
0
        private static void MakeLoopEnd(TokenizerOutput program, TLine line, Stack <LoopData> loopStack)
        {
            if (loopStack.Count < 1)
            {
                throw new TokenizerException(line, "Misplaced NEXT");
            }

            LoopData data = loopStack.Pop();
            var      next = (KwNext)line.Statement;

            if (data.LoopVariable.Name != next.Variable.Name)
            {
                throw new TokenizerException(line, "NEXT Error : Unknown variable " + next.Variable.Name);
            }

            // step 1: change the variable
            var add    = new NumBinaryOperator(data.LoopVariable, data.StepVariable, "+");
            var assign = new NumBinaryOperator(data.LoopVariable, add, "=");

            program.Program.Add(line.Clone(assign));

            // step 2: goto to the begining
            var gt = new KwrGoto(data.StartLine, true);

            program.Program.Add(line.Clone(gt));

            // change the top jump condition
            ((KwrJumpIfTrue)program.Program[data.StartLine].Statement).JumpPos = program.Program.Count;
        }
Ejemplo n.º 2
0
        private static void MakeBranch(TokenizerOutput program, TLine line, Stack <LoopData> loopStack)
        {
            var kwif  = (KwIf)line.Statement;
            var newIf = new KwrJumpIfNotTrue(kwif.Condition, -1);

            program.Program.Add(line.Clone(newIf));                 // placeholder

            foreach (Statement s in kwif.Statements)
            {
                TokenizeStatement(program, line.Clone(s), loopStack);
            }

            if (kwif.ElseStatements == null)
            {
                newIf.JumpPos = program.Program.Count;
            }
            else
            {
                var gt = new KwrGoto(-1, true);
                program.Program.Add(line.Clone(gt));
                newIf.JumpPos = program.Program.Count;

                foreach (Statement s in kwif.ElseStatements)
                {
                    TokenizeStatement(program, line.Clone(s), loopStack);
                }

                gt.JumpPos = program.Program.Count;
            }
        }