How about a combination of the two? 
if ( ref($var) && $var->isa("Some::Package") )
{
    $var->someMethod();
}

[download]
Or better yet: 
my $sub;
if ( ref($var) && ($sub = $var->can("someMethod")) )
{
    $sub->();
}
else
{
    die "Method someMethod not found."
}

[download]
Of course you don't have to capture the return of "can" but it can be convenient.

In reply to Re^2: How to tell if a variable is blessed ? by linux454
in thread How to tell if a variable is blessed ? by jeanluca

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