protected override Expression VisitBinary(BinaryExpression binaryExpression) { var left = this.Visit(binaryExpression.Left); var right = this.Visit(binaryExpression.Right); if (left.Type == binaryExpression.Left.Type && right.Type == binaryExpression.Right.Type) { return binaryExpression.ChangeLeftRight(left, right); } if (!IsTaskType(left.Type) && !IsTaskType(right.Type)) { return binaryExpression.ChangeLeftRight(left, right); } if (IsTaskType(left.Type) && IsTaskType(right.Type)) { var leftVar = Expression.Parameter(left.Type); var rightVar = Expression.Parameter(right.Type); var variables = new[] { leftVar, rightVar }; var expression = CreateChainedCalls(leftVar, rightVar); var lambda = Expression.Lambda(binaryExpression.ChangeLeftRight(Expression.Property(leftVar, "Result"), Expression.Property(rightVar, "Result")), Expression.Parameter(expression.Type)); return Expression.Block(variables, Expression.Assign(leftVar, left), Expression.Assign(rightVar, right), Expression.Call(expression, "ContinueWith", new[] { lambda.ReturnType }, lambda)); } if (this.IsTaskType(left.Type)) { var leftVar = Expression.Parameter(left.Type); var variables = new[] { leftVar }; var expression = CreateChainedCalls(leftVar); var lambda = Expression.Lambda(binaryExpression.ChangeLeftRight(Expression.Property(leftVar, "Result"), right), Expression.Parameter(expression.Type)); return Expression.Block(variables, Expression.Assign(leftVar, left), Expression.Call(expression, "ContinueWith", new[] { lambda.ReturnType }, lambda)); } if (this.IsTaskType(right.Type)) { var rightVar = Expression.Parameter(right.Type); var variables = new[] { rightVar }; var expression = CreateChainedCalls(rightVar); var lambda = Expression.Lambda(binaryExpression.ChangeLeftRight(left, Expression.Property(rightVar, "Result")), Expression.Parameter(expression.Type)); return Expression.Block(variables, Expression.Assign(rightVar, right), Expression.Call(expression, "ContinueWith", new[] { lambda.ReturnType }, lambda)); } return base.VisitBinary(binaryExpression); }