Vim is my editor of choice, reasonable so, whether it be for coding C++, LaTeX or even R. I’ve used RStudio, which even has a Vim-Mode, but I still prefer to use Vim. Vim has it’s own R plugin, namely Vim-R-plugin, but this post is about snippets. SnipMate is an awesome auto-completion plugin for Vim which is fully customizable. One simply writes a string, rnorm for example, and presses tab to autocomplete the code to rnorm(n=,mean=,sd=), where repeated press of tab cycles through the placeholders at the function parameters. The strings to recognize, referred to as snippets, are stored in a snippets file “languagetype.snippets” along with the corresponding code to auto-complete. These can be user defined for any language, not just R. It’s usually not necessary to write these snippets files yourself, as there are already existing snippets files within the vim community, including one for R. Here is a github repository containing snippets files for a great many languages, including R. Simply put this into your vim-SnipMate snippets directory. The last thing to do is to tell Vim to recognize an r filetype. If you open an R file and type,

:set ft=r

then this will tell Vim that the file is an R file. Obviously you don’t want to do this all the time, so to get Vim to automatically recognize “.r” and “.R” extensions as R files simply append your .vimrc file with:

au BufNewFile,BufRead *.r set filetype=r
au BufNewFile,BufRead *.R set filetype=r

Writing Custom Snippets

This is an example of how to complete a for loop having written only “for”. Append the r.snippets file with the following code.

snippet for
    for(${1:i} in ${2:begin}:${3:end}){
    ${4}
    }${5}

This defines “for” as the snippet, the string after which we will want to press tab. The dollar signs define the place holders. “${x:text}” defines the x’th placeholder and the highlighted text which will be replaced.

for<tab>

becomes

for(i in begin:end){

}

.

Repeated pressing of tab cycles between i, begin, end, body of foor loop and then breaks out of the for loop.

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