Random allocation list generator

Introduction I have made a random allocation list generator using R Shiny. It is located at https://icostatistics.shinyapps.io/randlist/). The source code is on github. Every now and then I get the request to make a random allocation list according to some specifications, usually for a randomised controlled trial (RCT). There are many R and Stata packages out there which does this, but I do this seldom enough to forget the specifications to the function calls.