Jonathan Turkanis wrote:
"Shannon Stewman" <stew@uchicago.edu> wrote in message news:20040304025205.GD832@uchicago.edu...
On Wed, Mar 03, 2004 at 01:34:50PM -0800, Powell, Gary wrote:
unsigned long n = std::accumulate( xs.begin(), xs.end(), 0UL, long (long lhs, X const &rhs) // inline fn with no
name.
{ return lhs + rhs.count; } );
This seems to cast out the type inference present in BLL. I think that's one of the nicer concepts in the lambda library, and a real boon to programming. In my limited experience with SML/OCaml, type inference seems a better, safer, and more convenient way to program, albeit requiring a lot more compiler intelligence. As BLL shows,
though,
this is quite possible, though perhaps limited, with existing C++.
How about:
unsigned long n = std::accumulate( xs.begin(), xs.end(), 0UL, auto(long lhs, const auto& rhs) // inline fn with no name. { return lhs + rhs.count; } );
I would prefer also eliding the argument types: unsigned long n = std::accumulate( xs.begin(), xs.end(), 0UL, lambda(lhs, rhs) { return lhs + rhs.count; } ); Most of the time, you also do not know the type of the arguments before hand. -- Joel de Guzman http://www.boost-consulting.com http://spirit.sf.net