Re: Lambdas, Overloading and Pattern matching
On 14 oct, 09:40, int...@gmail.com wrote:
It seems that it could be implemented as a library in C++0x:
<snip smart recursive inheritance />
template <class T>
void foo(const T& x)
{
std::string type_name =
match(x,
<>(int x)("int")
<>(float x)("float")
<>(...)("unknown")
);
}
Very nice syntax, and nice implementation too.
The above is a single example which only does pattern matching on
single values (but then so does boost::variant), and relies on the
presence of argument_type & result_type (but lambdas do provide that).
However, it seems to be quite possible to extend this to handle multi-
value patterns, and use decltype and variadic templates to decompose
signatures of function objects when argument_type & result_type are
not available, thus providing a fully generalised solution.
I don't really see how you can decompose signatures, could you
elaborate?
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