Question

I’m using a well known template to allow binary constants

template< unsigned long long N > struct binary {   enum { value = (N % 10) + 2 * binary< N / 10 > :: value } ; };  template<> struct binary< 0 > {   enum { value = 0 } ; }; 

So you can do something like binary<101011011>::value. Unfortunately this has a limit of 20 digits for a unsigned long long.

Does anyone have a better solution?

Answer 1

Does this work if you have a leading zero on your binary value? A leading zero makes the constant octal rather than decimal.

Which leads to a way to squeeze a couple more digits out of this solution – always start your binary constant with a zero! Then replace the 10’s in your template with 8’s.