dlib C++ Library - metaprogramming.cpp

// Copyright (C) 2008 Davis E. King (davis@dlib.net)
// License: Boost Software License See LICENSE.txt for the full license.
#include <sstream>
#include <string>
#include <cstdlib>
#include <ctime>
#include <dlib/algs.h>
#include <dlib/metaprogramming.h>
#include "tester.h"
namespace 
{
 using namespace test;
 using namespace dlib;
 using namespace std;
 logger dlog("test.metaprogramming");
 void metaprogramming_test (
 )
 /*!
 ensures
 - runs tests on template metaprogramming objects and functions for compliance with the specs 
 !*/
 { 
 print_spinner();
 DLIB_TEST(is_signed_type<signed char>::value == true);
 DLIB_TEST(is_signed_type<signed short>::value == true);
 DLIB_TEST(is_signed_type<signed int>::value == true);
 DLIB_TEST(is_signed_type<signed long>::value == true);
 DLIB_TEST(is_unsigned_type<signed char>::value == false);
 DLIB_TEST(is_unsigned_type<signed short>::value == false);
 DLIB_TEST(is_unsigned_type<signed int>::value == false);
 DLIB_TEST(is_unsigned_type<signed long>::value == false);
 DLIB_TEST(is_unsigned_type<unsigned char>::value == true);
 DLIB_TEST(is_unsigned_type<unsigned short>::value == true);
 DLIB_TEST(is_unsigned_type<unsigned int>::value == true);
 DLIB_TEST(is_unsigned_type<unsigned long>::value == true);
 DLIB_TEST(is_signed_type<unsigned char>::value == false);
 DLIB_TEST(is_signed_type<unsigned short>::value == false);
 DLIB_TEST(is_signed_type<unsigned int>::value == false);
 DLIB_TEST(is_signed_type<unsigned long>::value == false);
 COMPILE_TIME_ASSERT(is_signed_type<signed char>::value == true);
 COMPILE_TIME_ASSERT(is_signed_type<signed short>::value == true);
 COMPILE_TIME_ASSERT(is_signed_type<signed int>::value == true);
 COMPILE_TIME_ASSERT(is_signed_type<signed long>::value == true);
 COMPILE_TIME_ASSERT(is_unsigned_type<signed char>::value == false);
 COMPILE_TIME_ASSERT(is_unsigned_type<signed short>::value == false);
 COMPILE_TIME_ASSERT(is_unsigned_type<signed int>::value == false);
 COMPILE_TIME_ASSERT(is_unsigned_type<signed long>::value == false);
 COMPILE_TIME_ASSERT(is_unsigned_type<unsigned char>::value == true);
 COMPILE_TIME_ASSERT(is_unsigned_type<unsigned short>::value == true);
 COMPILE_TIME_ASSERT(is_unsigned_type<unsigned int>::value == true);
 COMPILE_TIME_ASSERT(is_unsigned_type<unsigned long>::value == true);
 COMPILE_TIME_ASSERT(is_signed_type<unsigned char>::value == false);
 COMPILE_TIME_ASSERT(is_signed_type<unsigned short>::value == false);
 COMPILE_TIME_ASSERT(is_signed_type<unsigned int>::value == false);
 COMPILE_TIME_ASSERT(is_signed_type<unsigned long>::value == false);
 }
 void test_call_if_valid() 
 {
 int value = 0;
 auto foo = [&](int a, int b) { value += a + b; };
 auto bar = [&](std::string) { value++; };
 auto baz = [&]() { value++; };
 DLIB_TEST(value == 0);
 DLIB_TEST(call_if_valid(baz));
 DLIB_TEST(value == 1);
 DLIB_TEST(!call_if_valid(foo));
 DLIB_TEST(value == 1);
 DLIB_TEST(!call_if_valid(bar));
 DLIB_TEST(value == 1);
 DLIB_TEST(call_if_valid(bar, "stuff"));
 DLIB_TEST(value == 2);
 DLIB_TEST(!call_if_valid(baz, "stuff"));
 DLIB_TEST(value == 2);
 DLIB_TEST(call_if_valid(foo, 3, 1));
 DLIB_TEST(value == 6);
 DLIB_TEST(!call_if_valid(bar, 3, 1));
 DLIB_TEST(value == 6);
 // make sure stateful lambdas are modified when called
 value = 0;
 int i = 0;
 auto stateful = [&value, i]() mutable { ++i; value = i; };
 DLIB_TEST(call_if_valid(stateful));
 DLIB_TEST(value == 1);
 DLIB_TEST(call_if_valid(stateful));
 DLIB_TEST(value == 2);
 DLIB_TEST(call_if_valid(stateful));
 DLIB_TEST(value == 3);
 }
 class metaprogramming_tester : public tester
 {
 public:
 metaprogramming_tester (
 ) :
 tester ("test_metaprogramming",
 "Runs tests on the metaprogramming objects and functions.")
 {}
 void perform_test (
 )
 {
 metaprogramming_test();
 test_call_if_valid();
 }
 } a;
}