Direct insertion of over 1000 symbols (e.g. currencies, letters, emojis, arrows, mathematical symbols and so on) into 'Rmarkdown' documents and 'Shiny' applications by incorporating 'HTML' hex codes.

First, install and load...
install.packages("r2symbols")
library("r2symbols")
One line code to transform entire document
# library call and setting at the top the document
library(r2symbols)
trans.r2symbols(font.color="green",font.weight = "bold",font.size = 30)
# within the text, add symbols
sample `alpha` text and `34` sample `u` text
#load library
library(r2symbols)
#apply global settings
symbol.setting(font.size=40,font.weight ="normal",font.color = "purple")
#start including in texts
symbol("alpha")
sym("naira","yen",font.size=30,font.weight ="bold",font.color = "red")
sym("heart")
symbol(23)
# you could use within the text without needing to declare trans.r2symbols()
sample `r symbol(23)` text and `r symbol('alpha')` sample `r sym('trademark')` text
View information about this at https://cran.r-project.org/web/packages/r2symbols
For a complete list of all the symbols and codes, please go to this link. Thank you.