Request Short Link
C++ 98
C++ 11
C++ 14
C++ 17
C++ 20
C++ 23
C++ 2c
for-loops as while-loops
array subscription
Show all implicit casts
Show all template parameters of a CallExpr
Use libc++
Transform std::initializer_list
Show noexcept internals
Show padding information
Show coroutine transformation
Show C++ to C transformation
Show object lifetime
Default
15
18
20
22
26
More
GitHub
Patreon
Issues
About
Policies
Examples
C++ Insights @ YouTube
Settings
Version
New C++ Insights Episode
×
Made by
Andreas Fertig
Powered by
Flask
and
CodeMirror
Source:
#include <type_traits> using std::integral_constant; using std::conditional_t; template <class ...Ts> struct sum; template <int n> struct fib : conditional_t<n<0, fib<0>, sum<fib<n-1>, fib<n-2>>> { }; template <> struct fib<1> : integral_constant<int, 1> { }; template <> struct fib<0> : integral_constant<int, 0> { }; template <class T, T ...N> struct sum<fib<N>...> : integral_constant<T, (fib<N>::value + ...)> { }; int main() { static_assert(fib<6>::value == 8); static_assert(fib<-900>::value == 0); return 0; }
Insight:
Console: