$myobject->ymd;

##</code><code>##

$myobject->ymd();

##</code><code>##

$myobject->ymd $foo;

##</code><code>##

$myobject->ymd($foo);

##</code><code>##

> perl -wle "$myobject = bless {}; $myobject->ymd $foo"
Scalar found where operator expected at -e line 1, near "->ymd $foo"

##</code><code>##

Can't locate object method "ymd" via package "123456"