Type mismatch in Win32::OLE method call with multiple args

mikewhit_ has asked for the wisdom of the Perl Monks concerning the following question:

Simple COM methods (none or single arg) seem to work OK, but get error message

Win32::OLE(0.1601) error 0x80020005: "Type mismatch"
    in METHOD/PROPERTYGET "FlashLamp" argument 1 at CS1.pm line 199
[download]

when calling interface method with (in my case) three args; callable OK from VB.

Is this a Win32::OLE calling issue with multiple args, or do I need to look elsewhere?

Perl code:

    $cs1 = Win32::OLE->GetActiveObject("CS.CSInterface1") or die "Coul
+d not get interface CS1\n";
    ...
    my ($on, $off, $count) = $_; # contains args !!! SHOULD USE ARRAY 
+HERE !!!
    $cs1->FlashLamp($on, $off, $count);
[download]

IDL:
[id(24), helpstring("method FlashLamp")] HRESULT FlashLamp([in] long OnDuration, [in] long OffDuration, [in] long FlashCount);

C++ code:

STDMETHODIMP CCSInterface1::FlashLamp(long OnDuration, long OffDuratio
+n, long FlashCount)
{
    return S_OK;
}
[download]

Platform stuff:
WinXP SP1, ActiveState Perl 5.8.0.804

Thanks.

Update
Thanks! I couldn't see the wood for the trees.
Doh! Shows my Perl is rusty from a couple of years of non-use !
Used some code from some earlier work where I'd had a ref to a list, so I'd have had to deref it first anyhow !

But used an array now instead and all is well.
Cheers.

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Re: Type mismatch in Win32::OLE method call with multiple args by VSarkiss (Monsignor) on Jan 13, 2005 at 16:52 UTC
The problem is here: `my ($on, $off, $count) = $_; # contains args` [download] You're assigning a scalar (`$_`) to a list. That will leave `$off` and `$count` as `undef`, which is what's causing the error. (Even `$on` can be undefined, if `$_` is.) The fix depends on what's in `$_`: whether you need to `split` it, or use a different variable (maybe `@_`), or ... . Update Added some clarification Do not rebuke them with harsh words ... but rather lead them gently - with URLs - so that they may learn wisdom.	[reply] [d/l] [select]

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Re: Type mismatch in Win32::OLE method call with multiple args
by VSarkiss (Monsignor) on Jan 13, 2005 at 16:52 UTC

The problem is here:

my ($on, $off, $count) = $_; # contains args
[download]

$_

$off

$count

undef

$on

$_

The fix depends on what's in $_: whether you need to split it, or use a different variable (maybe @_), or ... .

Update
Added some clarification

Do not rebuke them with harsh words ... but rather lead them gently - with URLs - so that they may learn wisdom.

[reply]
[d/l]
[select]