Generates C function stubs

c_prototype

function! GenPrototypes(reg)
  let fs=[]
  let l:space = '\_s\{-}'
  let l:keywd = '\(\(\w\+\s\+\)\+\)' . l:space ") #1
  let l:rtype = '\(\w\+\)'           . l:space ") #3
  let l:fname = '\(\w\+\)'           . l:space ") #4
  let l:parms = '\((.*)\)'           . l:space ") #5
  let l:block = '\({\_.\{-}}\)'
  let l:regex = l:keywd . l:rtype
  \           . l:fname . l:parms
  \           . l:block
  execute "normal /^" . l:regex . "/ge\<CR>"
  %s//\=len(add(fs, ( submatch(1) .
  \                   submatch(3) . " " .
  \                   submatch(4) . " " .
  \                   submatch(5) . ';' ))) ? submatch(0) : ''/ge
  let reg = empty(a:reg) ? 'f' : a:reg
  let l:joined = join(fs, "\n") . "\n"
  execute "let @".reg." = system(\"column -t\", l:joined)"
endfunction
command! -register GenPrototypes call GenPrototypes(<q-reg>)

function! InsertPrototypes(line)
  if a:0 > 0
    let line = a:line
  else
    let line = 0
  end
  call GenPrototypes('x')
  execute "normal! ".line.'gg | "fP'
endfunction
command! -register InsertPrototypes call InsertPrototypes(<q-args>)

output.c

/* Example output from InsertPrototypes */

static  inline  int32_t  fp_int_to_fp          (int      n);
static  inline  int      fp_fp_to_zero_int     (int32_t  x);
static  inline  int      fp_fp_to_nearest_int  (int32_t  x);
static  inline  int32_t  fp_add_fp_fp          (int32_t  x,   int32_t  y);
static  inline  int32_t  fp_add_fp_int         (int32_t  x,   int      n);
static  inline  int32_t  fp_mul_fp_fp          (int32_t  x,   int32_t  y);
static  inline  int32_t  fp_mul_fp_int         (int32_t  x,   int      n);
static  inline  int32_t  fp_div_int_int        (int      a,   int      b);
static  inline  int32_t  fp_div_fp_fp          (int32_t  x,   int32_t  y);