__GNU_PBDS::TREE(3cxx)

🌸 NAME 🌸

__gnu_pbds::tree< Key, Mapped, Cmp_Fn, Tag, Node_Update, _Alloc > — bestie, this is the tree-based container from libstdc++'s policy-based data structures, and it's lowkey iconic 💅

(okay and yes, this whole page lives in manual section 3cxx, the C++ library section — noted, moving on 🫶)

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✨ SYNOPSIS ✨

#include <assoc_container.hpp>

It inherits __gnu_pbds::basic_branch< Key, Mapped, Tag, Node_Update, Policy_Tl, _Alloc >. That's the family tree, fr fr 🌳

💖 Public Types

• typedef Cmp_Fn cmp_fn — the comparison functor type. This is the little guy that decides who comes before who ✨
• typedef Node_Update node_update — the node update thingy, straight up 🙈

🎀 Public Member Functions

• tree (const cmp_fn &c) — constructor that takes some policy objects. r_cmp_fn gets copied by the Cmp_Fn object of the container object, no cap 💫
• tree (const tree &other) — the copy constructor, it exists, that's the vibe 🫶
• 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, range construction 🎀
• template<typename It > tree (It first, It last, const cmp_fn &c) — same deal but with some policy objects too: the value_types between first_it and last_it get inserted into the container object, and r_cmp_fn gets copied by the cmp_fn object of the container object 💖
• tree & operator= (const tree &other) — assignment operator, present and accounted for 👑
• void swap (tree &other) — swaps with another tree, that's it, that's the whole function 🌈

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🦋 Detailed Description 🦋

So the full template situation is literally this:

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 it's described as "A tree-based container." — short, sweet, main character energy 👑

🌟 Template Parameters

• Key — Key type. iykyk 🔑
• Mapped — Map type.
• Cmp_Fn — Comparison functor.
• Tag — Instantiating data structure type, see container_tag.
• Node_Update — Updates tree internal-nodes, restores invariants when invalidated. The original literally drops a XXX See design::tree-based-containersnode invariants. here, so consider that note officially passed along, bestie 💀
• _Alloc — Allocator type.

The base tag choices are: ov_tree_tag, rb_tree_tag, splay_tree_tag. Pick your fighter ✨

And the base is basic_branch. Periodt.

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💅 Member Typedef Documentation 💅

🎀 cmp_fn

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

Comparison functor type. That's the entire description and honestly? It ate. 🍓

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⭐ Constructor & Destructor Documentation ⭐

💖 tree (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>>
__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. Obsessed with how specific that is 🫶

🦋 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. Give it a range, it fills itself, we love an independent queen 💅

🌈 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. Range plus policy, the full combo meal 🍓

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👑 Author 👑

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

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Heads up bestie: the not-quite-documented ones here — tree (const tree &other), tree & operator= (const tree &other) and void swap (tree &other) — come with no description in the original, so I'm not out here inventing lore for them 🙈

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And that's the whole page! Signing off from libstdc++, section 3cxx — Doxygen-generated, no date on the tin, still absolutely serving 🎀💖✨