__GNU_PBDS::TREE(3)

💖 __gnu_pbds::tree< Key, Mapped, Cmp_Fn, Tag, Node_Update, _Alloc > 💖

okay bestie so this is a page from the Library Functions Manual for libstdc++, section 3, and it's about the most ✨aesthetic✨ tree container GNU ever handed us. sit down, hydrate, let's get into it 🫶

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🌸 NAME 🌸

__gnu_pbds::tree< Key, Mapped, Cmp_Fn, Tag, Node_Update, _Alloc > — that's the whole name, that's the whole vibe, no notes 💅

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✨ SYNOPSIS ✨

#include <assoc_container.hpp>

it inherits from:

__gnu_pbds::basic_branch< Key, Mapped, Tag, Node_Update, Policy_Tl, _Alloc >

like. it's giving "I am a whole tree and I know it" 💀

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🎀 Public Types 🎀

• typedef Cmp_Fn cmp_fn — bestie this is literally just the comparison functor type, the thing that decides what comes before what 👑
• typedef Node_Update node_update — the node update type, no extra lore given, that's it, that's the tea 🍓

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🌸 Public Member Functions 🌸

• tree (const cmp_fn &c) — constructor that takes some policy objects! the r_cmp_fn you hand over gets copied by the Cmp_Fn object of the container object. yes girl, copied. 🫶
• tree (const tree &other) — the classic copy constructor, stealing your whole vibe (affectionately) 🦋
• template<typename It> tree (It first, It last) — constructor taking __iterators to a range of value_types. everything between first_it and last_it gets inserted into the container object. slay. ✨
• template<typename It> tree (It first, It last, const cmp_fn &c) — same range situation but now with policy objects too 🎀 everything between first_it and last_it goes into the container object, and r_cmp_fn gets copied by the cmp_fn object of the container object. two-for-one, iconic.
• tree & operator= (const tree &other) — assignment operator, the "you're me now" moment 😭
• void swap (tree &other) — swap the contents with other. trade. exchange. mutual glow-up. 🔥

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💫 Detailed Description 💫

okay here's the actual signature, verbatim, no cap:

template<typename Key, typename Mapped, typename Cmp_Fn = std::less<Key>,
    typename Tag = rb_tree_tag, template< typename Node_CItr, typename
    Node_Itr, typename Cmp_Fn_, typename _Alloc_ > class Node_Update =
    null_node_update, typename _Alloc = std::allocator<char>>
class __gnu_pbds::tree< Key, Mapped, Cmp_Fn, Tag, Node_Update, _Alloc >

and the description, and I quote: "A tree-based container." that's it. that's the whole description. absolute main character energy, said four words and left 💅

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🧚 Template Parameters 🧚

• Key — Key type. the actual key bestie 🔑
• Mapped — Map type. the thing being mapped 🗺️
• Cmp_Fn — Comparison functor. the referee of ordering ⭐
• Tag — Instantiating data structure type, see container_tag. this is the one that picks your tree's whole personality 🎀
• Node_Update — Updates tree internal-nodes, restores invariants when invalidated. XXX See design::tree-based-containersnode invariants. ⚠️
• _Alloc — Allocator type. handles the memory bag 💜

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Base tag choices are: ov_tree_tag, rb_tree_tag, splay_tree_tag.

and the base is basic_branch. periodt. 👑

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📎 Member Typedef Documentation 📎

so for this whole template situation:

template<typename Key, typename Mapped, typename Cmp_Fn = std::less<Key>,
    typename Tag = rb_tree_tag, template< typename Node_CItr, typename
    Node_Itr, typename Cmp_Fn_, typename _Alloc_ > class Node_Update =
    null_node_update, typename _Alloc = std::allocator<char>>
typedef Cmp_Fn __gnu_pbds::tree< Key, Mapped, Cmp_Fn, Tag, Node_Update, _Alloc >::cmp_fn

cmp_fn — Comparison functor type. and that's the whole note. she's brief, she's efficient, we love her 💖

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🔥 Constructor & Destructor Documentation 🔥

🫶 tree (const cmp_fn & c) — [inline]

full signature, exactly:

template<typename Key, typename Mapped, typename Cmp_Fn = std::less<Key>,
    typename Tag = rb_tree_tag, template< typename Node_CItr, typename
    Node_Itr, typename Cmp_Fn_, typename _Alloc_ > class Node_Update =
    null_node_update, typename _Alloc = std::allocator<char>>
__gnu_pbds::tree< Key, Mapped, Cmp_Fn, Tag, Node_Update, _Alloc >::tree
(const cmp_fn & c) [inline]

Constructor taking some policy objects. r_cmp_fn will be copied by the Cmp_Fn object of the container object. 💅

🦋 tree (It first, It last) — [inline]

template<typename Key, typename Mapped, typename Cmp_Fn = std::less<Key>,
    typename Tag = rb_tree_tag, template< typename Node_CItr, typename
    Node_Itr, typename Cmp_Fn_, typename _Alloc_ > class Node_Update =
    null_node_update, typename _Alloc = std::allocator<char>>
template<typename It> __gnu_pbds::tree< Key, Mapped, Cmp_Fn, Tag,
Node_Update, _Alloc >::tree (It first, It last) [inline]

Constructor taking __iterators to a range of value_types. The value_types between first_it and last_it will be inserted into the container object. inserting. slaying. same thing. ✨

🎀 tree (It first, It last, const cmp_fn & c) — [inline]

template<typename Key, typename Mapped, typename Cmp_Fn = std::less<Key>,
    typename Tag = rb_tree_tag, template< typename Node_CItr, typename
    Node_Itr, typename Cmp_Fn_, typename _Alloc_ > class Node_Update =
    null_node_update, typename _Alloc = std::allocator<char>>
template<typename It> __gnu_pbds::tree< Key, Mapped, Cmp_Fn, Tag,
Node_Update, _Alloc >::tree (It first, It last, const cmp_fn & c)
[inline]

Constructor taking __iterators to a range of value_types and some policy objects. The value_types between first_it and last_it will be inserted into the container object. r_cmp_fn will be copied by the cmp_fn object of the container object. two jobs, one constructor, she's booked and busy 😭💖

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👑 Author 👑

Generated automatically by Doxygen for libstdc++ from the source code. so like, a robot wrote this about a robot-built tree, and honestly? we stan a transparent origin story 🌈

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okay bestie that's the whole page, no facts left behind, every signature intact, every default preserved 🫶 this manual page came from libstdc++ and was lovingly auto-generated by Doxygen straight from the source code — so if anything's weird in here, blame the source, not me 💅✨