if obj isa String then return native_setopt_string(opt, obj)
if obj isa FileWriter then return native_setopt_file(opt, obj._file.as(not null))
if obj isa CURLSList then return native_setopt_slist(opt, obj)
if obj isa String then return native_setopt_string(opt, obj)
if obj isa FileWriter then return native_setopt_file(opt, obj._file.as(not null))
if obj isa CURLSList then return native_setopt_slist(opt, obj)