runtime/indent/ruby.vim

5 " URL:			http://vim-ruby.rubyforge.org
52 " Regex used for words that, at the start of a line, add a level of indent.
59 " Regex used for words that, at the start of a line, remove a level of indent.
63 " Regex that defines the start-match for the 'end' keyword.
98 " Check if the character at lnum:col is inside a string, comment, or is ascii.
214   " others we indent to the containing line's MSL's level.  Return -1 if fail.
234   " If we have a deindenting keyword, find its match and indent to its level.
267   " At the start of the file use zero indent.
276   " If the previous line ended with a block opening, add a level of indent.
322     " level
348   " If the MSL line had an indenting keyword in it, add a level of indent.
359   " If the previous line ended with [*+/.-=], indent one extra level.