I am quite bewildered by while a particular perl module can tell the difference between when it a function is use'd into scope and when it is called directly from the module name. In this example that I gave earlier in response to a question: 
#!/usr/bin/perl -w

use strict;
use Date::Calc qw(Add_Delta_Days);

my (undef, undef, undef, $day, $month,$year)  = localtime();
$year+=1900;
$month+=1;

($year,$month,$day) = Add_Delta_Days($year,$month,$day, -3);
print join("-", $year,$month,$day)

[download]
Works fine. But this: 
#!/usr/bin/perl -w

use strict;
use Date::Calc;

my (undef, undef, undef, $day, $month,$year)  = localtime();
$year+=1900;
$month+=1;

($year,$month,$day) = Date::Calc->Add_Delta_Days($year,$month,$day, -3
+);
print join("-", $year,$month,$day)

[download]
Doesn't work correctly. It throws a usage warning. (Keep in mind this throws the error even if I add the qw symbol import). Perhaps, I'm wrong, but I thought that specifying the scope with ModuleName->FunctionName didn't call the function any differently or with any different parameters.

Where's the bug? My code? My reasoning? The module?
Thanks for any guidance anyone can give.

    --jaybonci

In reply to Perl module symbol import versus direct invocation by JayBonci

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