std::regex_...rator++(int)(3)

🎀 std::regex_...rator++(int)(3) 🎀

okay so this page is from the C++ Standard Libary manual — yes, that spelling is literally on the page, bestie — and it's all about std::regex_iterator::operator++ and operator++(int). It's giving "advance the iterator to the next match" energy. ✨

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📛 NAME 📛

std::regex_iterator::operator++,operator++(int) — std::regex_iterator::operator++,operator++(int)

Yes, it says it twice. Iconic, honestly.

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✨ Synopsis ✨

          regex_iterator& operator++();      (since C++11)
          regex_iterator operator++( int );  (since C++11)

Advances the iterator on the next match.

🚧 This section is incomplete Reason: explain better

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okay so here's how the whole "next match" thing goes down. At first, a local variable of type BidirIt is constructed with the value of match[0].second.

If the iterator holds a zero-length match and start == end, then *this is set to the end-of-sequence iterator and the function returns.

Otherwise, if the iterator holds a zero-length match, the operator invokes the following:

          regex_search(start, end, match, *pregex,
                       flags | regex_constants::match_not_null |
                               regex_constants::match_continuous);

If the call returns true, the function returns.

Otherwise, the operator increments start and continues as if the most recent match was not a zero-length match.

If the most recent match was not a zero-length match, the operator sets flags to flags | regex_constants::match_prev_avail and invokes the following:

          regex_search(start, end, match, *pregex, flags);

If the call returns false, the iterator sets *this to the end-of-sequence iterator, and the function returns.

In all cases in which the call to regex_search returns true, match.prefix().first will be equal to the previous value of match[0].second, and for each index i in the range [0, match.size()) for which match[i].matched is true, match[i].position() will return distance(begin, match[i].first).

This means that match[i].position() gives the offset from the beginning of the target sequence, which is often not the same as the offset from the sequence passed in the call to regex_search.

It is unspecified how the implementation makes these adjustments. This means that a compiler may call an implementation-specific search function, in which case a user-defined specialization of regex_search will not be called.

⚠️ The behavior is undefined if the iterator is an end-of-sequence iterator. Do not do that, bestie. 💀

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🌸 Parameters 🌸

(none) — literally no parameters. Clean. Minimalist. We love to see it. 🫶

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💖 Return value 💖

1. *this
2. The previous value of the iterator.

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🏷️ Category 🏷️

• Todo with reason

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big sparkly sign-off energy: this cutie came from source/version http://cppreference.com, dated 2024.06.10 💅✨