string.h

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// Copyright (c) 2019 The Bitcoin Core developers
// Distributed under the MIT software license, see the accompanying
// file COPYING or http://www.opensource.org/licenses/mit-license.php.
 
#ifndef BITCOIN_UTIL_STRING_H
#define BITCOIN_UTIL_STRING_H
 
#include <span.h>
 
#include <array>
#include <cstdint>
#include <cstring>
#include <locale>
#include <sstream>
#include <string>
#include <string_view>
#include <vector>
 
namespace util {
void ReplaceAll(std::string &in_out, std::string_view search,
                std::string_view substitute);
 
template <typename T = Span<const char>>
std::vector<T> Split(const Span<const char> &sp, std::string_view separators) {
    std::vector<T> ret;
    auto it = sp.begin();
    auto start = it;
    while (it != sp.end()) {
        if (separators.find(*it) != std::string::npos) {
            ret.emplace_back(start, it);
            start = it + 1;
        }
        ++it;
    }
    ret.emplace_back(start, it);
    return ret;
}
 
template <typename T = Span<const char>>
std::vector<T> Split(const Span<const char> &sp, char sep) {
    return Split<T>(sp, std::string_view{&sep, 1});
}
 
[[nodiscard]] inline std::vector<std::string> SplitString(std::string_view str,
                                                          char sep) {
    return Split<std::string>(str, sep);
}
 
[[nodiscard]] inline std::vector<std::string>
SplitString(std::string_view str, std::string_view separators) {
    return Split<std::string>(str, separators);
}
 
[[nodiscard]] inline std::string_view
TrimStringView(std::string_view str, std::string_view pattern = " \f\n\r\t\v") {
    std::string::size_type front = str.find_first_not_of(pattern);
    if (front == std::string::npos) {
        return {};
    }
    std::string::size_type end = str.find_last_not_of(pattern);
    return str.substr(front, end - front + 1);
}
 
[[nodiscard]] inline std::string
TrimString(std::string_view str, std::string_view pattern = " \f\n\r\t\v") {
    return std::string(TrimStringView(str, pattern));
}
 
[[nodiscard]] inline std::string_view
RemovePrefixView(std::string_view str, std::string_view prefix) {
    if (str.substr(0, prefix.size()) == prefix) {
        return str.substr(prefix.size());
    }
    return str;
}
 
[[nodiscard]] inline std::string RemovePrefix(std::string_view str,
                                              std::string_view prefix) {
    return std::string(RemovePrefixView(str, prefix));
}
 
template <typename T, typename BaseType, typename UnaryOp>
auto Join(const std::vector<T> &list, const BaseType &separator,
          UnaryOp unary_op) -> decltype(unary_op(list.at(0))) {
    decltype(unary_op(list.at(0))) ret;
    for (size_t i = 0; i < list.size(); ++i) {
        if (i > 0) {
            ret += separator;
        }
        ret += unary_op(list.at(i));
    }
    return ret;
}
 
template <typename T, typename T2>
T Join(const std::vector<T> &list, const T2 &separator) {
    return Join(list, separator, [](const T &i) { return i; });
}
 
// Explicit overload needed for c_str arguments, which would otherwise cause a
// substitution failure in the template above.
inline std::string Join(const std::vector<std::string> &list,
                        std::string_view separator) {
    return Join<std::string>(list, separator);
}
 
inline std::string MakeUnorderedList(const std::vector<std::string> &items) {
    return Join(items, "\n",
                [](const std::string &item) { return "- " + item; });
}
 
[[nodiscard]] inline bool ContainsNoNUL(std::string_view str) noexcept {
    for (auto c : str) {
        if (c == 0) {
            return false;
        }
    }
    return true;
}
 
template <typename T> std::string ToString(const T &t) {
    std::ostringstream oss;
    oss.imbue(std::locale::classic());
    oss << t;
    return oss.str();
}
 
template <typename T1, size_t PREFIX_LEN>
[[nodiscard]] inline bool
HasPrefix(const T1 &obj, const std::array<uint8_t, PREFIX_LEN> &prefix) {
    return obj.size() >= PREFIX_LEN &&
           std::equal(std::begin(prefix), std::end(prefix), std::begin(obj));
}
} // namespace util
 
#endif // BITCOIN_UTIL_STRING_H