public void ExecuteForCommand() { ICommand setX = new SetVariableCommand("x", new ConstantExpression(0)); ICommand setY = new SetVariableCommand("y", new ConstantExpression(0)); List<ICommand> commands = new List<ICommand>(); commands.Add(setX); commands.Add(setY); ICommand initialCommand = new CompositeCommand(commands); IExpression condition = new CompareExpression(ComparisonOperator.Less, new VariableExpression("x"), new ConstantExpression(6)); IExpression addXtoY = new ArithmeticBinaryExpression(ArithmeticOperator.Add, new VariableExpression("y"), new VariableExpression("x")); ICommand addToY = new SetVariableCommand("y", addXtoY); ICommand endCommand = new SetVariableCommand("x", new ArithmeticBinaryExpression(ArithmeticOperator.Add, new VariableExpression("x"), new ConstantExpression(1))); ForCommand forcmd = new ForCommand(initialCommand, condition, endCommand, addToY); Context context = new Context(); context.SetValue("y", null); forcmd.Execute(context); Assert.AreEqual(15, context.GetValue("y")); }
private static ICallable BuildFactorialFunction(IContext context) { IExpression condition = new CompareExpression(ComparisonOperator.LessEqual, new VariableExpression("n"), new ConstantExpression(1)); ICommand return1 = new ReturnCommand(new ConstantExpression(1)); ICommand return2 = new ReturnCommand(new ArithmeticBinaryExpression(ArithmeticOperator.Multiply, new VariableExpression("n"), new InvokeExpression(new VariableExpression("Factorial"), new IExpression[] { new ArithmeticBinaryExpression(ArithmeticOperator.Subtract, new VariableExpression("n"), new ConstantExpression(1)) }))); ICommand ifcmd = new IfCommand(condition, return1, return2); ICallable factorial = new Function(new string[] { "n" }, ifcmd, context); return factorial; }
private IExpression ParseBinaryExpressionZerothLevel() { IExpression expression = this.ParseBinaryExpressionFirstLevel(); if (expression == null) return null; while (this.TryParse(TokenType.Operator, "<", ">", "==", ">=", "<=", "!=", "===", "!==")) { Token oper = this.lexer.NextToken(); IExpression right = this.ParseBinaryExpressionFirstLevel(); ComparisonOperator op = ComparisonOperator.Unknown; if (oper.Value == "<") op = ComparisonOperator.Less; if (oper.Value == ">") op = ComparisonOperator.Greater; if (oper.Value == "<=") op = ComparisonOperator.LessEqual; if (oper.Value == ">=") op = ComparisonOperator.GreaterEqual; if (oper.Value == "===") op = ComparisonOperator.Equal; if (oper.Value == "!==") op = ComparisonOperator.NotEqual; if (op == ComparisonOperator.Unknown) throw new ParserException(string.Format("Unknown operator '{0}'", oper.Value)); expression = new CompareExpression(op, expression, right); } return expression; }