> perl multiuse.pl
main:1: p=main{four=>"IV", one=>'I', three=>"III"}
main:2: Derived{five=>5, four=>"IV", one=>1.20, seven=>7.20, three=>"III", two=>2.20}

Decimal:p=Derived{five=>5, four=>"IV", one=>1.20, seven=>7.20, three=>"III", two=>2.20}
Decimal: (one, two, three)=(1, 2, change 3 to this txt)

Float:p=Derived{five=>5, four=>"IV", one=>1.20, seven=>7.20, three=>"III", two=>2.20}

assign to nine got:
Can't locate object method "nine" via package "Derived" at multiuse.pl line 37.
  eval {...} called at multiuse.pl line 37
  Derived::Float(Derived=HASH(0x8e5648)) called at multiuse.pl line 56

Float:q=Derived{five=>5, four=>"Float: Derived 4.4", one=>1.20, seven=>7.20, three=>"Float: 3.3", two=>2.20}