/*
This file is part of solidity.
solidity is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
solidity is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with solidity. If not, see <http://www.gnu.org/licenses/>.
*/
/** @file StringUtils.h
* @author Balajiganapathi S <balajiganapathi.s@gmail.com>
* @date 2017
*
* String routines
*/
#pragma once
#include <string>
#include <vector>
#include <libdevcore/CommonData.h>
namespace dev
{
// Calculates the Damerau–Levenshtein distance between _str1 and _str2 and returns true if that distance is not greater than _maxDistance
// if _lenThreshold > 0 and the product of the strings length is greater than _lenThreshold, the function will return false
bool stringWithinDistance(std::string const& _str1, std::string const& _str2, size_t _maxDistance, size_t _lenThreshold = 0);
// Calculates the Damerau–Levenshtein distance between _str1 and _str2
size_t stringDistance(std::string const& _str1, std::string const& _str2);
// Return a string having elements of suggestions as quoted, alternative suggestions. e.g. "a", "b" or "c"
std::string quotedAlternativesList(std::vector<std::string> const& suggestions);
/// Joins collection of strings into one string with separators between, last separator can be different.
/// @param _list collection of strings to join
/// @param _separator defaults to ", "
/// @param _lastSeparator (optional) will be used to separate last two strings instead of _separator
/// @example join(vector<string>{"a", "b", "c"}, "; ", " or ") == "a; b or c"
template<class T>
std::string joinHumanReadable
(
T const& _list,
std::string const& _separator = ", ",
std::string const& _lastSeparator = ""
)
{
auto const itEnd = end(_list);
std::string result;
for (auto it = begin(_list); it != itEnd; )
{
std::string element = *it;
bool first = (it == begin(_list));
++it;
if (!first)
{
if (it == itEnd && !_lastSeparator.empty())
result += _lastSeparator; // last iteration
else
result += _separator;
}
result += std::move(element);
}
return result;
}
/// Formats large numbers to be easily readable by humans.
/// Returns decimal representation for smaller numbers; hex for large numbers.
/// "Special" numbers, powers-of-two and powers-of-two minus 1, are returned in
/// formulaic form like 0x01 * 2**24 - 1.
/// @a T will typically by unsigned, u160, u256 or bigint.
/// @param _value to be formatted
/// @param _useTruncation if true, internal truncation is also applied,
/// like 0x5555...{+56 more}...5555
/// @example formatNumber((u256)0x7ffffff)
template <class T>
inline std::string formatNumberReadable(
T const& _value,
bool _useTruncation = false
)
{
static_assert(
std::is_same<bigint, T>::value || !std::numeric_limits<T>::is_signed,
"only unsigned types or bigint supported"
); //bigint does not carry sign bit on shift
// smaller numbers return as decimal
if (_value <= 0x1000000)
return _value.str();
HexCase hexcase = HexCase::Mixed;
HexPrefix prefix = HexPrefix::Add;
// when multiple trailing zero bytes, format as N * 2**x
int i = 0;
T v = _value;
for (; (v & 0xff) == 0; v >>= 8)
++i;
if (i > 2)
{
// 0x100 yields 2**8 (N is 1 and redundant)
if (v == 1)
return "2**" + std::to_string(i * 8);
return toHex(toCompactBigEndian(v), prefix, hexcase) +
" * 2**" +
std::to_string(i * 8);
}
// when multiple trailing FF bytes, format as N * 2**x - 1
i = 0;
for (v = _value; (v & 0xff) == 0xff; v >>= 8)
++i;
if (i > 2)
{
// 0xFF yields 2**8 - 1 (v is 0 in that case)
if (v == 0)
return "2**" + std::to_string(i * 8) + " - 1";
return toHex(toCompactBigEndian(T(v + 1)), prefix, hexcase) +
" * 2**" + std::to_string(i * 8) +
" - 1";
}
std::string str = toHex(toCompactBigEndian(_value), prefix, hexcase);
if (_useTruncation)
{
// return as interior-truncated hex.
int len = str.size();
if (len < 24)
return str;
const int initialChars = (prefix == HexPrefix::Add) ? 6 : 4;
const int finalChars = 4;
int numSkipped = len - initialChars - finalChars;
return str.substr(0, initialChars) +
"...{+" +
std::to_string(numSkipped) +
" more}..." +
str.substr(len-finalChars, len);
}
// otherwise, show whole value.
return str;
}
}
