From https://github.com/quarto-dev/quarto-r/issues/40

Simple `.qmd` document with only inline code syntax, starting with `r`

````markdown
`r ** 2`
````

This will be recognized as R inline code and knitr engine will be required. However, for users doing only markdown writing this is surprising.

Unfortunate syntax clash in our discovery.  

I don't know if we can do better, but I was thinking maybe only code cells should trigger engine - Will it be that common to only have R inline code in a document without a code cell in the document ? 

Anyway, probably worth considering if we can. 
cscheid
2023-01-09T21:34:08Z
cderv
v1.3
closed
Auto binding will use knitr engine when only a inline code syntax is in the doc
https://github.com/quarto-dev/quarto-cli/issues/3908