Gilad Bracha's been pushing for languages with optional type systems for some time: https://www.google.com/webhp?q=bracha+optional+type#safe=off&q=bracha+optio

Gilad Bracha's been pushing for languages with optional type systems for some time: https://www.google.com/webhp?q=bracha+optional+type#safe=off&q=bracha+optional+type https://www.google.com/webhp?q=bracha+optional+type#safe=off...