std::default_searcher(3)

💖 std::default_searcher(3) — C++ Standard Libary bestie edition 💖

Okay so you opened the manual page for std::default_searcher(3) from the C++ Standard Libary (yes, that’s the manual name, and we’re keeping it exactly like that, no cap). We’re gonna make this searcher make sense, fr fr. Slay.

💖 NAME 💖

std::default_searcher - std::default_searcher

That’s literally the whole name section. Iconic. No notes.

🌸 SYNOPSIS 🌸

Defined in header <functional>.

template< class ForwardIt, class BinaryPredicate = std::equal_to<> >
class default_searcher;

(since C++17)

A class suitable for use with the Searcher overload of std::search that delegates the search operation to the pre-C++17 standard library’s std::search.

std::default_searcher is CopyConstructible and CopyAssignable.

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🎀 MEMBER FUNCTIONS 🎀

💅 std::default_searcher::default_searcher

default_searcher( ForwardIt pat_first,
                  ForwardIt pat_last,
                  BinaryPredicate pred = BinaryPredicate() );

(since C++17) (until C++20)

constexpr default_searcher( ForwardIt pat_first,
                            ForwardIt pat_last,
                            BinaryPredicate pred = BinaryPredicate() );

(since C++20)

Constructs a std::default_searcher by storing copies of pat_first, pat_last, and pred.

🌈 PARAMETERS 🌈

• pat_first, pat_last — a pair of iterators designating the string to be searched for
• pred — a callable object used to determine equality

💀 EXCEPTIONS 💀

Any exceptions thrown by the copy constructors of BinaryPredicate or ForwardIt.

✨ std::default_searcher::operator() ✨

template< class ForwardIt2 >
std::pair<ForwardIt2, ForwardIt2>
operator()( ForwardIt2 first, ForwardIt2 last ) const;

(since C++17) (until C++20)

template< class ForwardIt2 >
constexpr std::pair<ForwardIt2, ForwardIt2>
operator()( ForwardIt2 first, ForwardIt2 last ) const;

(since C++20)

The member function called by the Searcher overload of std::search to perform a search with this searcher.

Returns a pair of iterators i, j, where i is std::search(first, last, pat_first, pat_last, pred) and j is std::next(i, std::distance(pat_first, pat_last)) unless std::search returned last (no match), in which case j equals last as well.

🍓 PARAMETERS 🍓

• first, last — a pair of iterators designating the string to be examined

👑 RETURN VALUE 👑

A pair of iterators to the first and one past last positions in [first, last) where a subsequence that compares equal to [pat_first, pat_last) as defined by pred is located, or a pair of copies of last otherwise.

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🦋 EXAMPLE 🦋

// Run this code

#include <algorithm>
#include <functional>
#include <iomanip>
#include <iostream>
#include <string_view>

int main()
{
    constexpr std::string_view in =
        "Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed "
        "do eiusmod tempor incididunt ut labore et dolore magna aliqua";

    const std::string_view needle{"pisci"};

    auto it = std::search(in.begin(), in.end(),
                  std::default_searcher(
                      needle.begin(), needle.end()));
    if (it != in.end())
        std::cout << "The string " << std::quoted(needle) << " found at offset "
                  << it - in.begin() << '\n';
    else
        std::cout << "The string " << std::quoted(needle) << " not found\n";
}

🌟 OUTPUT 🌟

The string "pisci" found at offset 43

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👀 SEE ALSO 👀

• search — searches for a range of elements (function template)
• boyer_moore_searcher — Boyer-Moore search algorithm implementation (C++17) (class template)
• boyer_moore_horspool_searcher — Boyer-Moore-Horspool search algorithm implementation (C++17) (class template)

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Source/version/date tea ☕: http://cppreference.com, 2024.06.10, and this page is std::default_searcher(3). Byeee, go search something cute 💖✨