mirror of
https://github.com/boostorg/safe_numerics.git
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80e17943ca
refined type requirements for integer vs numeric fixed bugs in safe literal added acknowledgement to documentation
42 lines
1.5 KiB
C++
42 lines
1.5 KiB
C++
#include <iostream>
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#include "../include/safe_range.hpp"
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#include "../include/safe_literal.hpp"
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#include "../include/native.hpp"
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#include "../include/exception.hpp"
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#include "safe_format.hpp" // prints out range and value of any type
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using namespace boost::numeric; // for safe_literal
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// create a type for holding small integers. We "know" that C++ type
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// promotion rules will work such that operations on this type
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// will never overflow. If change the program to break this, the
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// usage of the trap_exception promotion policy will prevent compilation.
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using safe_t = safe_signed_range<
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-24,
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82,
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native, // C++ type promotion rules work OK for this example
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trap_exception // catch problems at compile time
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>;
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auto f(const safe_t & x, const safe_t & y){
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//safe_t z = x + y; // depending on values of x & y COULD fail
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auto z = x + y; // due to C++ type promotion rules,
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// we know that this cannot fail
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std::cout << "(x + y) = " << safe_format(x + y) << std::endl;
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std::cout << "(x - y) = " << safe_format(x - y) << std::endl;
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return z;
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}
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int main(int argc, const char * argv[]){
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std::cout << "example 83:\n";
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// constexpr const safe_t z = 3; // fails to compile
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const safe_t x(safe_signed_literal<2>{});
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const safe_t y = safe_signed_literal<2>(); // to avoid runtime penalty
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std::cout << "x = " << safe_format(x) << std::endl;
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std::cout << "y = " << safe_format(y) << std::endl;
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std::cout << "z = " << safe_format(f(x, y)) << std::endl;
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return 0;
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}
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