toggleHump.vimrc

def CamelToSneak(name: string): string
  var l = []
  var start = true
  for ch in split(name, '\zs')
    if ch =~# '\u'
      l->add('_')
    endif
    l->add(tolower(ch))
  endfor
  var i = 0
  while l[i] == '_'
    i += 1
  endw
  return join(l[i :], '')
enddef

def SneakToCamel(name: string): string
  var ret = ''
  var pre_underscore = true
  for ch in split(name, '\zs')
    if ch == '_'
      pre_underscore = true
      continue
    endif
    if pre_underscore
      ret ..= toupper(ch)
      pre_underscore = false
    else
      ret ..= ch
    endif
  endfor
  return ret
enddef

def Convert(name: string): string
  return stridx(name, "_") == -1 ? CamelToSneak(name) : SneakToCamel(name)
enddef

def ConvertCword(all: bool=false)
  var cword = expand("<cword>")
  var pos = getcurpos()
  if all
    exec printf('g/\<%s\>/s/\<%s\>/%s/g', cword, cword, Convert(cword))
  else
    if has('clipboard')
      var __save1 = getreg('+')
      var __save2 = getreg('*')
    endif
    var __save3 = getreg('0')
    setreg('0', Convert(cword))
    norm! viw"0p
    if has('clipboard')
      setreg('+', __save1)
      setreg('*', __save2)
    endif
    setreg('0', __save3)
  endif
  setpos('.', pos)
enddef

map w <cmd>call <sid>ConvertCword(1)<cr>
map e <cmd>call <sid>ConvertCword()<cr>