exofast_expand_path.pro

;; replace environment variables with their values
function exofast_expand_path, string

  directories = strsplit(string,'/\',/extract)

  for i=0L, n_elements(directories)-1 do begin
     environment_variable_start = strpos(directories[i],'$')
     if environment_variable_start eq 0 then begin
        envvar = strmid(directories[i],1) ;; trim the $
        directories[i] = getenv(envvar)
     endif
  endfor

  path = strjoin(directories,path_sep())
  if strmid(string,0,1) eq path_sep() then path = path_sep() + path

  return, path

end