Annotate Ruby code in Vim with xmpfilter
rcodetools contains a utility called xmpfilter, which annotates Ruby code with intermediate results. This is great for testing ideas, explaining them to someone else, giving a live-coding talk, etc.
vim-ruby-xmpfilter provides Vim functions for xmpfilter.
First, we need to install rcodetools:
$ gem install rcodetools
Successfully installed rcodetools-0.8.5.0
1 gem installed
Then, add vim-ruby-xmpfilter to your Vim installation. My preferred way is with Vundle:
Bundle 't9md/vim-ruby-xmpfilter'
$ vim +BundleInstall +qall
$
Also, add mappings for keystrokes to your Vim config. I just stuck with F4/F5 suggested by the vim-ruby-xmpfilter README:
" xmpfilter
map <F4> <Plug>(xmpfilter-mark)
map <F5> <Plug>(xmpfilter-run)
Now we can open any Ruby file and start playing:
1 + 2
Press F4 to annotate the line:
1 + 2 # =>
And then F5 to update all annotations in the file:
1 + 2 # => 3