jslint.vim が微妙だったから代わりの syntax checker を探してたら見つけた。これすごい。

Syntastic comes in two parts: the syntax checker plugins, and the core script
(i.e. syntastic.vim). The syntax checker plugins are defined on a per-filetype
basis where each one wraps up an external syntax checking program. The core
script delegates off to these plugins and uses their output to provide the
syntastic functionality. At the time of this writing, syntax checking plugins
exist for c, coffee, cpp, css, cucumber, cuda, docbk, erlang, eruby, fortran,
go, haml, haskell, html, javascript, less, lua, matlab, perl, php, puppet,
python, ruby, sass/scss, sh, tcl, tex, vala, xhtml, xml, xslt, zpt

syntastic/doc/syntastic.txt at master · scrooloose/syntastic · GitHub

How to use syntastic