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// Copyright (C) 2016-2020 Jonathan Müller <jonathanmueller.dev@gmail.com>
// This file is subject to the license terms in the LICENSE file
// found in the top-level directory of this distribution.
#include <iostream>
#include <type_safe/narrow_cast.hpp> // narrow_cast<>
#include <type_safe/types.hpp> // boolean<>, integer<>, floating_point<>, aliases
namespace ts = type_safe;
// ts::unsigned_t is alias for ts::integer<unsigned>
// function is type safe - only unsigned integer types smaller than unsigned can be passed to the
// function
void only_unsigned(ts::unsigned_t val)
{
std::cout << "only_unsigned() got: " << val << '\n';
}
int main()
{
using namespace ts::literals; // for the literal operators
//=== type safe boolean ===//
// ts::bool_t is alias for ts::boolean
ts::bool_t b1(true);
// ts::bool_t b2; // error: no default constructor
// ts::bool_t b3(0); // error: 0 is not a bool
std::cout << "boolean value: " << b1 << '\n';
ts::bool_t b4 = !b1;
if (b4)
std::cout << "b4 is true\n";
else
std::cout << "b4 is false\n";
// b4 + 0; // error: arithmetic not possible
// ++b4; // error: arithmetic not possible
//=== type safe integer ===//
// ts::int_t is alias for ts::integer<int>
// ts::unsigned_t is alias for ts::integer<unsigned>
ts::int_t i1(0);
// ts::int_t i2; // error: no default constructor
// ts::int_t i3(100ll); // error: long long -> int would be narrowing
ts::unsigned_t u1(0u);
// ts::unsigned_t u2; // error: no default constructor
// ts::unsigned_t u3(0); // error: 0 is signed
std::cout << "integer value: " << i1 << ' ' << u1 << '\n';
i1 += 4;
ts::integer<long long> i4 = i1 + 100ll; // 100ll is long long, so result is long long
std::cout << i4 << '\n';
// --u1; // runtime error: unsigned underflow
// -u1; // error: no unary minus for unsigned
ts::uint8_t u4(255_u8); // instead of std::uint8_t(255)
// u4 += 2; // error: 2 is signed
// u4 += 2_u8; // runtime error: unsigned overflow
// only_unsigned(-4); // error: -4 is not unsigned
// only_unsigned(10); // error: 10 is not unsigned
// only_unsigned(i1); // error: i1 is not unsigned
only_unsigned(u4);
ts::unsigned_t u5 = ts::make_unsigned(i1);
// ts::unsigned_t u6 = ts::make_unsigned(-i1); // runtime error: value does not fit
ts::unsigned_t u7 = ts::abs(-i1); // but this works and returns an the unsigned integer
std::cout << u5 << ' ' << u7 << '\n';
// ts::int8_t i5 = ts::make_signed(u4); // runtime error: value does not fit
ts::int8_t i6 = ts::make_signed(u4 - 200_u8);
std::cout << i6 << '\n';
//=== type safe floating points ===//
// ts::float_t is alias for ts::floating_point<std::float_t> (std::float_t is float)
// ts::double_t is alias for ts::floating_point<std::double_t> (std::double_t is double)
ts::float_t f1(0.f);
// ts::float_t f2; // error: no default constructor
// ts::float_t f3(0.); // error: 0. is double literal
ts::double_t d1(0.);
// ts::double_t d2; // error: no default constructor
ts::double_t d3(0.f); // okay: float -> double is allowed
std::cout << "floating point value: " << f1 << ' ' << d1 << ' ' << d3 << '\n';
// f1++; // error: no in/decrement for floats
// f1 == 0.f; // error: no equality comparison for floats
//=== narrow cast ===//
ts::uint32_t uint32_val(325_u32);
// ts::uint8_t uint8_val1 =
// ts::narrow_cast<ts::uint8_t>(uint32_val); // runtime error: value does not fit
uint32_val = 100_u32;
ts::uint8_t uint8_val2 = ts::narrow_cast<ts::uint8_t>(uint32_val); // works
std::cout << uint32_val << ' ' << uint8_val2 << '\n';
ts::double_t double_val(0.1);
// ts::float_t float_val1 =
// ts::narrow_cast<ts::float_t>(double_val); // runtime error: 0.1 is not exact
double_val = 0.5;
ts::float_t float_val2 = ts::narrow_cast<ts::float_t>(double_val); // works, 0.5 is exact
std::cout << double_val << ' ' << float_val2 << '\n';
}
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