Brackets in .Rmd code blocks

Question

I am making some R markdown documents for my stats class. I've noticed I get an error in some functions when I have a code block with {r} instead of just r. Like so...

``` r
this code will be fine
``` 

``` {r}
this code will have an error
```

When should I be using the brackets for codeblocks in .Rmd and when should I leave them out?

Answer 1

Does it work without a space between the ``` and the {r}? It may be that the Rmd processor is getting confused about the spaces, but ignoring the bare r, and assuming the code is R by default.

The examples here don't have spaces:

https://rmarkdown.rstudio.com/lesson-3.html