libcxx/test/std/numerics/rand/rand.dist/rand.dist.pois/rand.dist.pois.exp/ctor_double.pass.cpp

   1 //===----------------------------------------------------------------------===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8
   9 // <random>
  10
  11 // template<class RealType = double>
  12 // class exponential_distribution
  13
  14 // explicit exponential_distribution(RealType lambda = 1.0);     // before C++20
  15 // exponential_distribution() : exponential_distribution(1.0) {} // C++20
  16 // explicit exponential_distribution(RealType lambda);           // C++20
  17
  18 #include <random>
  19 #include <cassert>
  20
  21 #include "test_macros.h"
  22 #if TEST_STD_VER >= 11
  23 #include "make_implicit.h"
  24 #include "test_convertible.h"
  25 #endif
  26
  27 template <class T>
  28 void test_implicit() {
  29 #if TEST_STD_VER >= 11
  30   typedef std::exponential_distribution<T> D;
  31   static_assert(test_convertible<D>(), "");
  32   assert(D(1) == make_implicit<D>());
  33   static_assert(!test_convertible<D, T>(), "");
  34 #endif
  35 }
  36
  37 int main(int, char**)
  38 {
  39     {
  40         typedef std::exponential_distribution<> D;
  41         D d;
  42         assert(d.lambda() == 1);
  43     }
  44     {
  45         typedef std::exponential_distribution<> D;
  46         D d(3.5);
  47         assert(d.lambda() == 3.5);
  48     }
  49
  50     test_implicit<float>();
  51     test_implicit<double>();
  52
  53     return 0;
  54 }