Vim: dynamic syntax

I want to dynamically (ie, depending on the content of the current file) adapt syntax highlighting. While this might be useful in general, my specific setting is as follows:

The kind of files I consider may contain (arbitrary many) blocks of the form (VAR ...) , where such "VAR-blocks" contain a space-separated list of identifiers that should be considered as variables (while identifiers that are not in a VAR-block are considered to be fixed function symbols or constants). Furthermore, there is already a file trs.vim that takes care of syntax highlighting for such files. In trs.vim a syntax group trsKeyword is declared. Now my goal is to highlight all variables using this group.

Consider the following example (lets call it add.trs ):

(VAR x y)(RULES
  add(z, y) -> y  
  add(s(x), y) -> s(add(x, y))
)

When opening add.trs in vim, I want that x and y are printed as keywords (whereas for example z is not, despite having no arguments).

---

I already achieved the desired result (but wanted to share it on SO). So here it is (the following snippets should be combined in a file vars.vim ).

First I define a pattern that will recognize VAR-blocks:

" pattern that matches VAR-blocks of *.trs files
let varblock = '(VARs*(.*))'

Then I check the current file (maybe there is a better way than using % for that?) for VAR-blocks and ignore the case where no match was found.

" create list of variables from all VAR-blocks 
try
  silent exe "vimgrep /" . varblock . "/j %"
catch /^Vim%((a+))=:E480/ " no match
  " do nothing
endtry

The found matches are obtained by getqfilst() , which I copy. Then I replace every element in this list by the first subgroup that matched the varblock pattern (which will be a string containing space-separated identifiers). I join all such strings into a single one and then split it at spaces to get a list of identifiers:

let vars = split(join(map(copy(getqflist()), 'matchlist(v:val.text, varblock)[1]')))

Finally I create a pattern matching these identifiers and register it to the trsKeyword group:

" activate syntax highlighting for variables
exe "syn match trsKeyword "<(" . join(vars, '|') . ")>""
" echo "variables: " . join(vars, ", ")

To make it work together with trs.vim I created the directory ~/.vim/syntax/trs and put trs.vim as well as vars.vim inside. Then in my ~/.vimrc I added

" TRS files
au BufNewFile,BufRead,BufWrite *.trs setf trs

which activates syntax highlighting for files ending with .trs (and also updates the list of variables whenever a buffer is saved).

链接地址: http://www.djcxy.com/p/52360.html

上一篇: 反引号，解开引号，引号，解开序列？

下一篇: Vim：动态语法