disabling unary "-" for unsigned types

[bearophile]

> Ideally in base 10 underscores can be syntactically allowed only every 3 digits and in base 2 or 6 every 4,8,16,32,16 digits only),

Sorry, I meant:

Ideally in base 10 underscores can be syntactically allowed only every 3 digits (starting from the less significant) and in base 2,8 or 16 every 4,8,16,32,64, etc, digits only),

Bye,
bearophile