ARCHIVE/rippled
1
0
Fork 0
mirror of https://github.com/XRPLF/rippled.git synced 2025-11-28 06:55:50 +00:00
Code Issues Packages Projects Releases Wiki Activity

Add beast::tagged_integer:

Browse Source 
* Wraps standard integer types to provide type-safety
 * Named types provide self-documenting semantics
 * Catches programmer errors involving mismatched types at compile time
 * Operators restrict mutation to only safe and meaningful operations
This commit is contained in:
Nik Bougalis
2014-03-21 09:31:15 -07:00
committed by Vinnie Falco
parent c0dfbdc910
commit a45b532664
3 changed files with 402 additions and 0 deletions
Download Patch File Download Diff File Expand all files Collapse all files

1
beast/utility/Utility.cpp
View File

@@ -32,3 +32,4 @@
#include "tests/bassert.test.cpp"
#include "tests/empty_base_optimization.test.cpp"
#include "tests/Zero.test.cpp"
#include "tests/tagged_integer.test.cpp"

247
beast/utility/tagged_integer.h Normal file
View File

@@ -0,0 +1,247 @@
//------------------------------------------------------------------------------
/*
This file is part of Beast: https://github.com/vinniefalco/Beast
Copyright 2014, Nikolaos D. Bougalis <nikb@bougalis.net>
Permission to use, copy, modify, and/or distribute this software for any
purpose with or without fee is hereby granted, provided that the above
copyright notice and this permission notice appear in all copies.
THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
ANY SPECIAL , DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
//==============================================================================
#ifndef BEAST_UTILITY_TAGGED_INTEGER_H_INCLUDED
#define BEAST_UTILITY_TAGGED_INTEGER_H_INCLUDED
#include "../container/hash_append.h"
#include "noexcept.h"
#include <functional>
#include <iostream>
#include <type_traits>
#include <utility>
namespace beast {
/** A type-safe wrap around standard unsigned integral types
The tag is used to implement type safety, catching mismatched types at
compile time. Multiple instantiations wrapping the same underlying integral
type are distinct types (distinguished by tag) and will not interoperate.
A tagged_integer supports all the comparison operators that are available
for the underlying integral type. It only supports a subset of arithmetic
operators, restricting mutation to only safe and meaningful types.
*/
template <class Int, class Tag>
class tagged_integer
{
private:
friend struct is_contiguously_hashable<tagged_integer <Int, Tag>>;
static_assert (std::is_unsigned <Int>::value,
"The specified Int type must be unsigned");
Int m_value;
public:
typedef Int value_type;
typedef Tag tag_type;
tagged_integer() = default;
template <
class OtherInt,
class = typename std::enable_if <
std::is_integral <OtherInt>::value &&
sizeof (OtherInt) <= sizeof (Int)
>::type
>
explicit
/* constexpr */
tagged_integer (OtherInt value) noexcept
: m_value (value)
{
}
// Arithmetic operators
tagged_integer&
operator++ () noexcept
{
++m_value;
return *this;
}
tagged_integer
operator++ (int) noexcept
{
tagged_integer orig (*this);
++(*this);
return orig;
}
tagged_integer&
operator-- () noexcept
{
--m_value;
return *this;
}
tagged_integer
operator-- (int) noexcept
{
tagged_integer orig (*this);
--(*this);
return orig;
}
template <class OtherInt>
typename std::enable_if <
std::is_integral <OtherInt>::value &&
sizeof (OtherInt) <= sizeof (Int),
tagged_integer <Int, Tag>>::type&
operator+= (OtherInt rhs) noexcept
{
m_value += rhs;
return *this;
}
template <class OtherInt>
typename std::enable_if <
std::is_integral <OtherInt>::value &&
sizeof (OtherInt) <= sizeof (Int),
tagged_integer <Int, Tag>>::type&
operator-= (OtherInt rhs) noexcept
{
m_value -= rhs;
return *this;
}
template <class OtherInt>
friend
typename std::enable_if <
std::is_integral <OtherInt>::value &&
sizeof (OtherInt) <= sizeof (Int),
tagged_integer <Int, Tag>>::type
operator+ (tagged_integer const& lhs,
OtherInt rhs) noexcept
{
return tagged_integer (lhs.m_value + rhs);
}
template <class OtherInt>
friend
typename std::enable_if <
std::is_integral <OtherInt>::value &&
sizeof (OtherInt) <= sizeof (Int),
tagged_integer <Int, Tag>>::type
operator+ (OtherInt lhs,
tagged_integer const& rhs) noexcept
{
return tagged_integer (lhs + rhs.m_value);
}
template <class OtherInt>
friend
typename std::enable_if <
std::is_integral <OtherInt>::value &&
sizeof (OtherInt) <= sizeof (Int),
tagged_integer <Int, Tag>>::type
operator- (tagged_integer const& lhs,
OtherInt rhs) noexcept
{
return tagged_integer (lhs.m_value - rhs);
}
friend
Int
operator- (tagged_integer const& lhs,
tagged_integer const& rhs) noexcept
{
return lhs.m_value - rhs.m_value;
}
// Comparison operators
friend
bool
operator== (tagged_integer const& lhs,
tagged_integer const& rhs) noexcept
{
return lhs.m_value == rhs.m_value;
}
friend
bool
operator!= (tagged_integer const& lhs,
tagged_integer const& rhs) noexcept
{
return lhs.m_value != rhs.m_value;
}
friend
bool
operator< (tagged_integer const& lhs,
tagged_integer const& rhs) noexcept
{
return lhs.m_value < rhs.m_value;
}
friend
bool
operator<= (tagged_integer const& lhs,
tagged_integer const& rhs) noexcept
{
return lhs.m_value <= rhs.m_value;
}
friend
bool
operator> (tagged_integer const& lhs,
tagged_integer const& rhs) noexcept
{
return lhs.m_value > rhs.m_value;
}
friend
bool
operator>= (tagged_integer const& lhs,
tagged_integer const& rhs) noexcept
{
return lhs.m_value >= rhs.m_value;
}
friend
std::ostream&
operator<< (std::ostream& s, tagged_integer const& t)
{
s << t.m_value;
return s;
}
friend
std::istream&
operator>> (std::istream& s, tagged_integer& t)
{
s >> t.m_value;
return s;
}
};
template <class Int, class Tag>
struct is_contiguously_hashable<tagged_integer<Int, Tag>>
: public is_contiguously_hashable<Int>
{
};
}
#endif

154
beast/utility/tests/tagged_integer.test.cpp Normal file
View File

@@ -0,0 +1,154 @@
//------------------------------------------------------------------------------
/*
This file is part of Beast: https://github.com/vinniefalco/Beast
Copyright 2014, Nikolaos D. Bougalis <nikb@bougalis.net>
Permission to use, copy, modify, and/or distribute this software for any
purpose with or without fee is hereby granted, provided that the above
copyright notice and this permission notice appear in all copies.
THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
ANY SPECIAL , DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
//==============================================================================
#if BEAST_INCLUDE_BEASTCONFIG
#include "../../../BeastConfig.h"
#endif
#include <type_traits>
#include "../tagged_integer.h"
#include "../../unit_test/suite.h"
namespace beast {
class tagged_integer_test
: public unit_test::suite
{
private:
struct Tag1 { };
struct Tag2 { };
typedef tagged_integer <std::uint32_t, Tag1> TagInt1;
typedef tagged_integer <std::uint32_t, Tag2> TagInt2;
typedef tagged_integer <std::uint64_t, Tag1> TagInt3;
// Check construction of tagged_integers
static_assert (std::is_constructible<TagInt1, std::uint32_t>::value,
"TagInt1 should be constructible using a std::uint32_t");
static_assert (!std::is_constructible<TagInt1, std::uint64_t>::value,
"TagInt1 should not be constructible using a std::uint64_t");
static_assert (std::is_constructible<TagInt3, std::uint32_t>::value,
"TagInt3 should be constructible using a std::uint32_t");
static_assert (std::is_constructible<TagInt3, std::uint64_t>::value,
"TagInt3 should be constructible using a std::uint64_t");
// Check assignment of tagged_integers
static_assert (!std::is_assignable<TagInt1, std::uint32_t>::value,
"TagInt1 should not be assignable with a std::uint32_t");
static_assert (!std::is_assignable<TagInt1, std::uint64_t>::value,
"TagInt1 should not be assignable with a std::uint64_t");
static_assert (!std::is_assignable<TagInt3, std::uint32_t>::value,
"TagInt3 should not be assignable with a std::uint32_t");
static_assert (!std::is_assignable<TagInt3, std::uint64_t>::value,
"TagInt3 should not be assignable with a std::uint64_t");
static_assert (std::is_assignable<TagInt1, TagInt1>::value,
"TagInt1 should be assignable with a TagInt1");
static_assert (!std::is_assignable<TagInt1, TagInt2>::value,
"TagInt1 should not be assignable with a TagInt2");
static_assert (std::is_assignable<TagInt3, TagInt3>::value,
"TagInt3 should be assignable with a TagInt1");
static_assert (!std::is_assignable<TagInt1, TagInt3>::value,
"TagInt1 should not be assignable with a TagInt3");
static_assert (!std::is_assignable<TagInt3, TagInt1>::value,
"TagInt3 should not be assignable with a TagInt1");
// Check convertibility of tagged_integers
static_assert (!std::is_convertible<std::uint32_t, TagInt1>::value,
"std::uint32_t should not be convertible to a TagInt1");
static_assert (!std::is_convertible<std::uint32_t, TagInt3>::value,
"std::uint32_t should not be convertible to a TagInt3");
static_assert (!std::is_convertible<std::uint64_t, TagInt3>::value,
"std::uint64_t should not be convertible to a TagInt3");
static_assert (!std::is_convertible<std::uint64_t, TagInt2>::value,
"std::uint64_t should not be convertible to a TagInt2");
static_assert (!std::is_convertible<TagInt1, TagInt2>::value,
"TagInt1 should not be convertible to TagInt2");
static_assert (!std::is_convertible<TagInt1, TagInt3>::value,
"TagInt1 should not be convertible to TagInt3");
static_assert (!std::is_convertible<TagInt2, TagInt3>::value,
"TagInt2 should not be convertible to a TagInt3");
public:
void run ()
{
TagInt1 const zero (0);
TagInt1 const one (1);
testcase ("Comparison Operators");
expect (zero >= zero, "Should be greater than or equal");
expect (zero == zero, "Should be equal");
expect (one > zero, "Should be greater");
expect (one >= zero, "Should be greater than or equal");
expect (one != zero, "Should not be equal");
unexpected (one < zero, "Should be greater");
unexpected (one <= zero, "Should not be greater than or equal");
unexpected (one == zero, "Should not be equal");
testcase ("Arithmetic Operators");
TagInt1 tmp;
tmp = zero + 0u;
expect (tmp == zero, "Should be equal");
tmp = 1u + zero;
expect (tmp == one, "Should be equal");
expect(--tmp == zero, "Should be equal");
expect(tmp++ == zero, "Should be equal");
expect(tmp == one, "Should be equal");
expect(tmp-- == one, "Should be equal");
expect(tmp == zero, "Should be equal");
expect(++tmp == one, "Should be equal");
tmp = zero;
tmp += 1u;
expect(tmp == one, "Should be equal");
tmp -= 1u;
expect(tmp == zero, "Should be equal");
}
};
BEAST_DEFINE_TESTSUITE(tagged_integer,utility,beast);
} // beast