We have an OLE server we've developed with Delphi (C++ builder actually). It has some methods with optional parameters. The ones with explicit defaults are fine, but the Type Library Editor does not allow a default for object (pointer) parameters (presumably because it knows they should be NULL). These parameters are causing problems with Win32::OLE in perl.

Here are the Win32::OLE->LastError()s for a method with an optional 2nd parameter:

$OleObj->Method($strFirstArg) gives:
Win32::OLE(0.1709) error 0x80020005: "Type mismatch"
    in METHOD/PROPERTYGET "ExportIntegrationByCells" argument 1

$OleObj->Method($strFirstArg, undef) gives:
Win32::OLE(0.1709) error 0x80020005: "Type mismatch"
    in METHOD/PROPERTYGET "ExportIntegrationByCells" argument 2

$OleObj->Method($strFirstArg, {Parameter2Name => undef}) gives:
Win32::OLE(0.1709) error 0x80020005: "Type mismatch"
    in METHOD/PROPERTYGET "ExportIntegrationByCells" argument "Paramet
+er2Name"

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The hideous VB script manages if I put a Nothing as the 2nd argument, surely Perl should do better ;-?

In reply to OLE optional parameter required by Anonymous Monk

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