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 <iostream> template<int v, int d> struct HasDivisorGE { static constexpr bool value = []{ if constexpr (d >= v) { return false; } else if constexpr (v % d == 0) { return true; } else { return HasDivisorGE<v, d + 1>::value; } }(); }; template<int v> struct IsPrime { static const bool value = !HasDivisorGE<v, 2>::value; }; int main() { std::cout << 7 << " : " << IsPrime<7>::value << std::endl; std::cout << 2000 << " : " << IsPrime<2000>::value << std::endl; // fatal error: template instantiation depth exceeds maximum of 900 // (use ‘-ftemplate-depth=’ to increase the maximum) // std::cout << 2003 << " : " << IsPrime<2003>::value << std::endl; return 0; }
Insight:
Console: