Error: unexpected '$' in " shiny::runApp('r/app.R', port=$"

[durraniu]

I created my first shiny-react app after running npx create-shiny-react-app my_shiny_react_app and responding to the prompts. Then I installed the dependencies and finally ran npm run dev, but I got:

> my_shiny_react_app@0.1.0 dev
> concurrently --kill-others-on-fail -c "cyan.bold,magenta.bold" -n "BUILD,SHINY" "npm run watch" "npm run shinyapp"

[BUILD] 
[BUILD] > my_shiny_react_app@0.1.0 watch
[BUILD] > concurrently --kill-others-on-fail -c "cyan.bold,green.bold" -n "TSC,BUILD" "tsc --noEmit --watch --preserveWatchOutput" "tsx build.ts --watch"
[BUILD] 
[SHINY] 
[SHINY] > my_shiny_react_app@0.1.0 shinyapp
[SHINY] > Rscript -e "options(shiny.autoreload = TRUE); shiny::runApp('r/app.R', port=${PORT:-8000})"
[SHINY] 
[SHINY] Error: unexpected '$' in " shiny::runApp('r/app.R', port=$"
[SHINY] Execution halted
[SHINY] npm run shinyapp exited with code 1
--> Sending SIGTERM to other processes..   
[BUILD] npm run watch exited with code 1

After changing the port to simply port=8000, the app ran successfully.