let get_file_type filename =
try
match get_suffix filename with
| "html" | "htm" -> Html
| "txt" | "text" -> Text
| s ->
Metrics_parameters.Metrics.fatal
"Unknown file extension %s. Cannot produce output.@." s
with
| No_suffix ->
Metrics_parameters.Metrics.fatal
"File %s has no suffix. Cannot produce output.@." filename