__GNU_DEBUG::_SAFE_FORWARD_LIST(3)

✨ NAME ✨

__gnu_debug::_Safe_forward_list< _SafeSequence > — bestie, it's giving special iterators, swap, and invalidation for forward_list 💅 and the whole reason it needs its own little class is the before_begin iterator. iykyk 🦋

This page lives in the Library Functions Manual section, and it's part of libstdc++. 🫶

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🌸 SYNOPSIS 🌸

#include <forward_list>

Inherits __gnu_debug::_Safe_sequence< _SafeSequence >.

Inherited by __gnu_debug::_Safe_container< forward_list, _Alloc, __gnu_debug::_Safe_forward_list >.

👑 Public Member Functions

• constexpr void _M_invalidate_if (_Predicate __pred) const — the invalidator, but make it constexpr ✨
• void _M_transfer_from_if (const _Safe_sequence &__from, _Predicate __pred) const — transfers the iterators that match, no cap 💖

🎀 Public Attributes

• _Safe_iterator_base * _M_const_iterators — the list of constant iterators that reference this container. 💜
• _Safe_iterator_base * _M_iterators — the list of mutable iterators that reference this container. 🔥
• unsigned int _M_version — the container version number. this number may never be 0 💀 fr fr.

🦋 Protected Member Functions

• void _M_detach_all () const
• void _M_detach_singular () const
• __gnu_cxx::__mutex & _M_get_mutex () const noexcept
• void _M_invalidate_all () const
• void _M_revalidate_singular () const
• void _M_swap (const _Safe_forward_list &) const noexcept
• void _M_swap (const _Safe_sequence_base &__x) const noexcept

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🌈 Detailed Description 🌈

template<typename _SafeSequence>
class __gnu_debug::_Safe_forward_list< _SafeSequence >

okay so the vibe here is: special iterators swap and invalidation for forward_list — and it's all because of that before_begin iterator. that's the whole plot bestie, no notes 💅✨

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💖 Member Function Documentation 💖

• void __gnu_debug::_Safe_sequence_base::_M_detach_all () const [protected], [inherited] — detaches all the iterators, which leaves them singular. they're on their own now, main character energy but alone 😭
• void __gnu_debug::_Safe_sequence_base::_M_detach_singular () const [protected], [inherited] — detaches all the singular iterators.
  • Postcondition: for all iterators i attached to this sequence, i->_M_version == _M_version. ✅
• __gnu_cxx::__mutex & __gnu_debug::_Safe_sequence_base::_M_get_mutex () const [protected], [noexcept], [inherited] — for use in _Safe_sequence. that's it, that's the description, it's giving mysterious 🧚
• void __gnu_debug::_Safe_sequence< _SafeSequence >::_M_invalidate_if (_Predicate __pred) const [inline], [constexpr], [inherited] — invalidates every iterator x that references this sequence, is not singular, and for which __pred(x) returns true. and heads up: __pred gets invoked with the normal iterators nested in the safe ones. 💅
• void __gnu_debug::_Safe_sequence_base::_M_revalidate_singular () const [protected], [inherited] — revalidates all attached singular iterators. this one's the glow-up method: it can be used to validate iterators that were invalidated before but, for some reason (like an exception 🫠), need to become valid again. slay, redemption arc 💖
• void __gnu_debug::_Safe_sequence_base::_M_swap (const _Safe_sequence_base & __x) const [protected], [noexcept], [inherited] — swaps this sequence with the given sequence. and not just the sequences, bestie — this operation also swaps ownership of the iterators, so when it's done, all iterators that originally referenced one container now reference the other container. full identity swap, no cap 👑
• void __gnu_debug::_Safe_sequence< _SafeSequence >::_M_transfer_from_if (const _Safe_sequence< _SafeSequence > & __from, _Predicate __pred) const [inherited] — transfers every iterator x that references the __from sequence, is not singular, and for which __pred(x) returns true. same deal as before: __pred gets invoked with the normal iterators nested in the safe ones.
  • References: _M_iterators.

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🍓 Member Data Documentation 🍓

• _Safe_iterator_base* __gnu_debug::_Safe_sequence_base::_M_const_iterators [mutable], [inherited] — the list of constant iterators that reference this container. 💜
• _Safe_iterator_base* __gnu_debug::_Safe_sequence_base::_M_iterators [mutable], [inherited] — the list of mutable iterators that reference this container.
  • Referenced by: _M_transfer_from_if(). 🔗
• unsigned int __gnu_debug::_Safe_sequence_base::_M_version [mutable], [inherited] — the container version number. and again for the people in the back: this number may never be 0 💀

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🫶 Author 🫶

Generated automatically by Doxygen for libstdc++ from the source code. not a human author, just the robot doing its thing 🤖✨

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and that's the whole page bestie!! 🌈💖 this little slice of the libstdc++ manual came straight from the libstdc++ source, page name __gnu_debu...Sequence >(3) (the long name got trimmed in the header, tragic but iconic 🙈), and it's the Library Functions Manual edition. go forth and swap your iterators responsibly, ily 🎀🦋👑