microsoft / RTVS

R Tools for Visual Studio.
MIT License
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typo in Rmd chunk definition produces confusing error message #4297

Open mkoohafkan opened 6 years ago

mkoohafkan commented 6 years ago

I made a stupid typo and defined a chunk as

```{r]

i.e., I accidentally ended the chunk header with a square bracket ] instead of a curly brace }.

Code in the chunk is still highlighted correctly and the chunk has the standard grey background color etc. RTVS doesn't detect a coding error there either. When I try to run the chunk with Ctrl+Alt+C I get the error message

Index was outside the bounds of the array

Which doesn't really indicate the problem.

It might be helpful to improve the error message, or do a slightly more robust check that chunk header syntax is correct.

MikhailArkhipov commented 6 years ago

Out of bounds error is a bug obviously. The other part is semi by design. R code begins after {r since { } block can contain list of arguments. So highlight remains even if block is terminated by ']' or not terminated at all - highlight includes all R code from { to the closing triple tick.