Set folding method for c and cpp files, but not h and hpp

Question

I am in the process of customizing my vim setup, and since I write a lot in C, I have a whole function dedicated just for those files, which I call with autocmd filetype c,cpp,h,hpp call C_syntax().

The issue I'm having is that I want auto folding to occur on .c and .cpp files, but not .h and .hpp files. In order to do this, I have tried:

function C_syntax()
    autocmd filetype c,cpp setlocal foldmethod=syntax
    "---snip---
endfunction

which disables folding for all files (.c and .cpp included), as well as this:

autocmd filetype c,cpp,h,hpp call C_syntax()
autocmd filetype c,cpp setlocal foldmethod=syntax

which enables it for .h and .hpp files as well.

How would I go about enabling the folding for only .c and .cpp files?

Thanks for any help

Answer 1

In a c ftplugin, check (:h :if) for the extension of the current buffer (with : h expand ()). If you match a header file don't set the option. Otherwise do.

You can define the thing with autocommands, but it's easy to get it wrong, beside it doesn't scale well

Answer 2

You can define the autocommands using the file extension instead of the filetype as following:

autocmd BufNewFile,BufRead *.c,*.cpp,*.h,*.hpp call C_syntax()
autocmd BufNewFile,BufRead *.c,*.cpp setlocal foldmethod=syntax