templates - Variadic functions (without arguments!) -

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let's assume want in c++0x:

size_t count_int() { return 0; } template<typename t, typename... tn> size_t count_int(t a0, tn... an) {     size_t n = is_integer<t>::value ? 1 : 0;     return n + count_int(an...); }

nice, feels unnecessary pass around arguments. unfortunately, not work:

size_t count_int() { return 0; } template<typename t, typename... tn> size_t count_int() {     size_t n = is_integer<t>::value ? 1 : 0;     return n + count_int<tn...>(); }

gcc complains error: no matching function call 'count_int()' in next-to-last line. why , how can fixed? thanks.

this works:

template <typename t> size_t count_int() {    return is_integer<t>::value ? 1 : 0; }  template<typename t, typename t1, typename... tn> size_t count_int() {     size_t n = is_integer<t>::value ? 1 : 0;     return n + count_int<t1,tn...>(); };

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