reactive | Tiny reactive template engine | Reactive Programming library

I am querying a database for an item using R2DBC and Spring Integration. I want to extend the transaction boundary a bit to include a handler - if the handler fails I want to roll back the database operation. But I'm having difficulty even establishing transactionality explicitly in my integration flow. The flow is defined as

I have a custom slide toggle component created using Angular Material. I followed this guide: https://material.angular.io/guide/creating-a-custom-form-field-control

Everything seems to be working fine except when I dynamically disable the custom component like this:

I have the following piece of code in a shiny app. My goal is to generate the choices for the "cutFamily2" selectInput widget based on what the user chose for the "machine2" selectInput.

If I use corte2() instead of eval(paste0("corte",2)) on the observerEvent the app runs properly. The problem is that I want to use the paste0() because the integer "2" in eval(paste0("corte",2)) will be an argument of a function (function(data,n)) so I can easily generate corte1, corte2 and so on.

When I run it using eval(paste0("corte",2)) I am getting the "error in $: $ operator is invalid for atomic vectors" and the app won't even run. I tried to use enframe() to convert it to a tibble, then the app runs, but I get a "Unknown or uninitialised column: CutFamily" error and the SelectInput choices will be empty. I also tried [[ instead, but nothing.

Any ideas on how to solve the problem?

I'm doing a project on Shiny where there are several drop-down menus. The options contained in the menus are stored in a data frame and when running the app you have the option to add more data to the data frame. The behavior I expected was that the options in the drop-down menu would automatically update with changes in the data frame, but this doesn't happen.

Is this possible to be done in Shiny? If yes, how?

Here's a code with an example of how I'm doing.

I want to deal with an abstraction where I can store f1, f2, f3, f4, f5... where

When running the first "almost MWE" code immediately below, which uses conditional panels and a "renderUI" function in the server section, it only runs correctly when I comment out the 3rd line from the bottom, observeEvent(vector.final(periods(),yield_input()),{yield_vector.R <<- unique(vector.final(periods(),yield_input()))}). If I run the code with this line activated, it crashes and I get the error message Error in [: subscript out of bounds which per my research means it is trying to access an array out of its boundary.

I am trying to create a component for a popover using Bootstrap4 in Vue:

I have an app such that after a user has selected input in tab 1, the app will redirect the user to tab 2, where a plot is generated based on the input selected in tab 1. I added suspendWhenHidden = FALSE so that the plot will be generated before the user is redirected to tab 2. However, when I added the following line of code, outputOptions(output, "mtcarsplot", suspendWhenHidden = FALSE), the console shows a warning.

Can anyone explain/solve the error in the code? Thanks for the help. I have added the code and then the warning message below.

the app's code (MWE):

I get this most common error message in shiny app. I am well aware of this error and have resolved it dozens of time. But this time I am stumped.