And here I was trying to have fun :D and you're all Basic debugging checklist and brian's Guide to Solving Any Perl Problem :)

Ok, doit warns a pair of objects ... typical wxWidgets, its always throwing objects at you :)

Wx::Frame=HASH(0x11d6a04) Wx::DropFilesEvent=SCALAR(0x12e59b4)
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Naturally with help of wxperl_usage / wxperl-usage / wxPerl::Usage / Class Method Browser , available methods, method invocation syntax, link to docs

I come upon
http://docs.wxwidgets.org/trunk/classwx_drop_files_event.html
http://docs.wxwidgets.org/2.8.12/wx_wxdropfilesevent.html

Which list things like

wxDropFilesEvent::GetFiles

wxString* GetFiles() const

Returns an array of filenames.

wxDropFilesEvent::GetNumberOfFiles

int GetNumberOfFiles() const

Returns the number of files dropped.
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Funny thing wxperl_usage also lists those things

Usage: Wx::DropFilesEvent::GetFiles(THIS)
$THIS->GetFiles()
Usage: Wx::DropFilesEvent::GetNumberOfFiles(THIS)
$THIS->GetNumberOfFiles()
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