__GNU_PBDS::CC_HASH_TABLE(3cxx)

💖 NAME 💖

Header vibes: __gnu_pbds::cc..._Hash, _Alloc >, manual section (3cxx) — but the actual star of the show is __gnu_pbds::cc_hash_table< Key, Mapped, Hash_Fn, Eq_Fn, Comb_Hash_Fn, Resize_Policy, Store_Hash, _Alloc >. Bestie, this is the 3cxx manual page for GNU PBDS's collision-chaining hash-based associative container, and it is lowkey iconic. Part 1 of 2, keep your wig on. 🎀

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✨ SYNOPSIS ✨

#include <assoc_container.hpp>

Inherits __gnu_pbds::basic_hash_table< Key, Mapped, Hash_Fn, Eq_Fn, Resize_Policy, Store_Hash, Tag, Policy_Tl, _Alloc >.

🎀 Public Types 🎀

• typedef Comb_Hash_Fn comb_hash_fn — the combining hash functor type, slaying under the name comb_hash_fn.
• typedef cc_hash_tag container_category — the container category tag, and it's cc_hash_tag.
• typedef Eq_Fn eq_fn — the equality functor type, living as eq_fn.
• typedef Hash_Fn hash_fn — the hashing functor type, aka hash_fn.
• typedef Resize_Policy resize_policy — the resize policy type, serving looks as resize_policy.

💅 Public Member Functions 💅

• cc_hash_table () — default constructor. No args, just main-character energy.
• cc_hash_table (const cc_hash_table &other) — copy constructor from other.
• cc_hash_table (const hash_fn &h) — constructor taking some policy objects. r_hash_fn will be copied by the Hash_Fn object of the container object.
• cc_hash_table (const hash_fn &h, const eq_fn &e) — constructor taking some policy objects. r_hash_fn will be copied by the hash_fn object of the container object, and r_eq_fn will be copied by the eq_fn object of the container object.
• cc_hash_table (const hash_fn &h, const eq_fn &e, const comb_hash_fn &ch) — constructor taking some policy objects. r_hash_fn will be copied by the hash_fn object of the container object, r_eq_fn will be copied by the eq_fn object of the container object, and r_comb_hash_fn will be copied by the comb_hash_fn object of the container object.
• cc_hash_table (const hash_fn &h, const eq_fn &e, const comb_hash_fn &ch, const resize_policy &rp) — constructor taking some policy objects. r_hash_fn will be copied by the hash_fn object of the container object, r_eq_fn will be copied by the eq_fn object of the container object, r_comb_hash_fn will be copied by the comb_hash_fn object of the container object, and r_resize_policy will be copied by the resize_policy object of the container object.
• template<typename It > cc_hash_table (It first, It last) — 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.
• template<typename It > cc_hash_table (It first, It last, const hash_fn &h) — 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.
• template<typename It > cc_hash_table (It first, It last, const hash_fn &h, const eq_fn &e) — 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_hash_fn will be copied by the hash_fn object of the container object, and r_eq_fn will be copied by the eq_fn object of the container object.
• template<typename It > cc_hash_table (It first, It last, const hash_fn &h, const eq_fn &e, const comb_hash_fn &ch) — 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_hash_fn will be copied by the hash_fn object of the container object, r_eq_fn will be copied by the eq_fn object of the container object, and r_comb_hash_fn will be copied by the comb_hash_fn object of the container object.
• template<typename It > cc_hash_table (It first, It last, const hash_fn &h, const eq_fn &e, const comb_hash_fn &ch, const resize_policy &rp) — 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_hash_fn will be copied by the hash_fn object of the container object, r_eq_fn will be copied by the eq_fn object of the container object, r_comb_hash_fn will be copied by the comb_hash_fn object of the container object, and r_resize_policy will be copied by the resize_policy object of the container object.
• cc_hash_table & operator= (const cc_hash_table &other) — assignment operator from other.
• void swap (cc_hash_table &other) — swaps with other.

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💫 Detailed Description 💫

Okay so the class template is giving "I have a lot of defaults and I'm not sorry":

template<typename Key, typename Mapped, typename Hash_Fn = typename
    detail::default_hash_fn<Key>::type, typename Eq_Fn = typename
    detail::default_eq_fn<Key>::type, typename Comb_Hash_Fn =
    detail::default_comb_hash_fn::type, typename Resize_Policy = typename
    detail::default_resize_policy<Comb_Hash_Fn>::type, bool Store_Hash =
    detail::default_store_hash, typename _Alloc = std::allocator<char>>
class __gnu_pbds::cc_hash_table< Key, Mapped, Hash_Fn, Eq_Fn,
       Comb_Hash_Fn, Resize_Policy, Store_Hash, _Alloc >

A collision-chaining hash-based associative container. Periodt. 💅

🧚 Template Parameters 🧚

• Key — Key type.
• Mapped — Map type.
• Hash_Fn — Hashing functor.
• Eq_Fn — Equal functor.
• Comb_Hash_Fn — Combining hash functor. If Hash_Fn is not null_type, then this is the ranged-hash functor; otherwise, this is the range-hashing functor. XXX(See Design::Hash-Based Containers::Hash Policies.)
• Resize_Policy — Resizes hash.
• Store_Hash — Indicates whether the hash value will be stored along with each key. If Hash_Fn is null_type, then the container will not compile if this value is true.
• _Alloc — Allocator type.

Base tag choices are: cc_hash_tag.

Base is basic_hash_table.

🛠️ Constructor & Destructor Documentation

Okay bestie, this is the part where we actually build the thing 💅 Nine constructors, all of them [inline], and literally every single one of them starts with the exact same giant template header. So here's that header, in full, one time as a reference — then every constructor below keeps it verbatim, because we do not skip details in this house 🫶

template<typename Key , typename Mapped , typename Hash_Fn  = typename
    detail::default_hash_fn<Key>::type, typename Eq_Fn  = typename
    detail::default_eq_fn<Key>::type, typename Comb_Hash_Fn  =
    detail::default_comb_hash_fn::type, typename Resize_Policy  = typename
    detail::default_resize_policy<Comb_Hash_Fn>::type, bool Store_Hash =
    detail::default_store_hash, typename _Alloc  = std::allocator<char>>

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cc_hash_table() — the default one ✨

template<typename Key , typename Mapped , typename Hash_Fn  = typename
    detail::default_hash_fn<Key>::type, typename Eq_Fn  = typename
    detail::default_eq_fn<Key>::type, typename Comb_Hash_Fn  =
    detail::default_comb_hash_fn::type, typename Resize_Policy  = typename
    detail::default_resize_policy<Comb_Hash_Fn>::type, bool Store_Hash =
    detail::default_store_hash, typename _Alloc  = std::allocator<char>>
__gnu_pbds::cc_hash_table< Key, Mapped, Hash_Fn, Eq_Fn, Comb_Hash_Fn,
Resize_Policy, Store_Hash, _Alloc >::cc_hash_table () [inline]

Default constructor. That's it, that's the whole vibe — no arguments, no fuss, just a fresh little container ready to be filled 🎀

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cc_hash_table(const hash_fn & h) — one policy, please 🌸

template<typename Key , typename Mapped , typename Hash_Fn  = typename
    detail::default_hash_fn<Key>::type, typename Eq_Fn  = typename
    detail::default_eq_fn<Key>::type, typename Comb_Hash_Fn  =
    detail::default_comb_hash_fn::type, typename Resize_Policy  = typename
    detail::default_resize_policy<Comb_Hash_Fn>::type, bool Store_Hash =
    detail::default_store_hash, typename _Alloc  = std::allocator<char>>
__gnu_pbds::cc_hash_table< Key, Mapped, Hash_Fn, Eq_Fn, Comb_Hash_Fn,
Resize_Policy, Store_Hash, _Alloc >::cc_hash_table (const hash_fn & h) [inline]

Constructor taking some policy objects. r_hash_fn will be copied by the Hash_Fn object of the container object. (Yes, it takes h and the docs call it r_hash_fn — that's just how it is, iykyk 😭)

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cc_hash_table(const hash_fn & h, const eq_fn & e) — policy duo 🦋

template<typename Key , typename Mapped , typename Hash_Fn  = typename
    detail::default_hash_fn<Key>::type, typename Eq_Fn  = typename
    detail::default_eq_fn<Key>::type, typename Comb_Hash_Fn  =
    detail::default_comb_hash_fn::type, typename Resize_Policy  = typename
    detail::default_resize_policy<Comb_Hash_Fn>::type, bool Store_Hash =
    detail::default_store_hash, typename _Alloc  = std::allocator<char>>
__gnu_pbds::cc_hash_table< Key, Mapped, Hash_Fn, Eq_Fn, Comb_Hash_Fn,
Resize_Policy, Store_Hash, _Alloc >::cc_hash_table (const hash_fn & h,
const eq_fn & e) [inline]

Constructor taking some policy objects. r_hash_fn will be copied by the hash_fn object of the container object, and r_eq_fn will be copied by the eq_fn object of the container object. Two policies, both slotted in, no notes 💅

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cc_hash_table(const hash_fn & h, const eq_fn & e, const comb_hash_fn & ch) — policy trio 💖

template<typename Key , typename Mapped , typename Hash_Fn  = typename
    detail::default_hash_fn<Key>::type, typename Eq_Fn  = typename
    detail::default_eq_fn<Key>::type, typename Comb_Hash_Fn  =
    detail::default_comb_hash_fn::type, typename Resize_Policy  = typename
    detail::default_resize_policy<Comb_Hash_Fn>::type, bool Store_Hash =
    detail::default_store_hash, typename _Alloc  = std::allocator<char>>
__gnu_pbds::cc_hash_table< Key, Mapped, Hash_Fn, Eq_Fn, Comb_Hash_Fn,
Resize_Policy, Store_Hash, _Alloc >::cc_hash_table (const hash_fn & h,
const eq_fn & e, const comb_hash_fn & ch) [inline]

Constructor taking some policy objects. r_hash_fn will be copied by the hash_fn object of the container object, r_eq_fn will be copied by the eq_fn object of the container object, and r_comb_hash_fn will be copied by the comb_hash_fn object of the container object. Look at us, collecting policies like Pokémon ✨

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cc_hash_table(const hash_fn & h, const eq_fn & e, const comb_hash_fn & ch, const resize_policy & rp) — the full policy stack 👑

template<typename Key , typename Mapped , typename Hash_Fn  = typename
    detail::default_hash_fn<Key>::type, typename Eq_Fn  = typename
    detail::default_eq_fn<Key>::type, typename Comb_Hash_Fn  =
    detail::default_comb_hash_fn::type, typename Resize_Policy  = typename
    detail::default_resize_policy<Comb_Hash_Fn>::type, bool Store_Hash =
    detail::default_store_hash, typename _Alloc  = std::allocator<char>>
__gnu_pbds::cc_hash_table< Key, Mapped, Hash_Fn, Eq_Fn, Comb_Hash_Fn,
Resize_Policy, Store_Hash, _Alloc >::cc_hash_table (const hash_fn & h,
const eq_fn & e, const comb_hash_fn & ch, const resize_policy & rp) [inline]

Constructor taking some policy objects. r_hash_fn will be copied by the hash_fn object of the container object, r_eq_fn will be copied by the eq_fn object of the container object, r_comb_hash_fn will be copied by the comb_hash_fn object of the container object, and r_resize_policy will be copied by the resize_policy object of the container object. All four, all copied, main character energy fr fr 🔥

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cc_hash_table(It first, It last) — feed it a range 🍓

template<typename Key , typename Mapped , typename Hash_Fn  = typename
    detail::default_hash_fn<Key>::type, typename Eq_Fn  = typename
    detail::default_eq_fn<Key>::type, typename Comb_Hash_Fn  =
    detail::default_comb_hash_fn::type, typename Resize_Policy  = typename
    detail::default_resize_policy<Comb_Hash_Fn>::type, bool Store_Hash =
    detail::default_store_hash, typename _Alloc  = std::allocator<char>>
template<typename It > __gnu_pbds::cc_hash_table< Key, Mapped, Hash_Fn,
Eq_Fn, Comb_Hash_Fn, Resize_Policy, Store_Hash, _Alloc >::cc_hash_table
(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. Snack-sized constructor: hand it a range, it eats the range 🧚

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cc_hash_table(It first, It last, const hash_fn & h) — range + hash policy 🌈

template<typename Key , typename Mapped , typename Hash_Fn  = typename
    detail::default_hash_fn<Key>::type, typename Eq_Fn  = typename
    detail::default_eq_fn<Key>::type, typename Comb_Hash_Fn  =
    detail::default_comb_hash_fn::type, typename Resize_Policy  = typename
    detail::default_resize_policy<Comb_Hash_Fn>::type, bool Store_Hash =
    detail::default_store_hash, typename _Alloc  = std::allocator<char>>
template<typename It > __gnu_pbds::cc_hash_table< Key, Mapped, Hash_Fn,
Eq_Fn, Comb_Hash_Fn, Resize_Policy, Store_Hash, _Alloc >::cc_hash_table
(It first, It last, const hash_fn & h) [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. Range first, policy second, chaos zero 💜

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cc_hash_table(It first, It last, const hash_fn & h, const eq_fn & e) — range + two policies 🎀

template<typename Key , typename Mapped , typename Hash_Fn  = typename
    detail::default_hash_fn<Key>::type, typename Eq_Fn  = typename
    detail::default_eq_fn<Key>::type, typename Comb_Hash_Fn  =
    detail::default_comb_hash_fn::type, typename Resize_Policy  = typename
    detail::default_resize_policy<Comb_Hash_Fn>::type, bool Store_Hash =
    detail::default_store_hash, typename _Alloc  = std::allocator<char>>
template<typename It > __gnu_pbds::cc_hash_table< Key, Mapped, Hash_Fn,
Eq_Fn, Comb_Hash_Fn, Resize_Policy, Store_Hash, _Alloc >::cc_hash_table
(It first, It last, const hash_fn & h, const eq_fn & e) [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_hash_fn will be copied by the hash_fn object of the container object, and r_eq_fn will be copied by the eq_fn object of the container object. (Yes, the original sentence really does run straight on into "The value_types…" with no period — we're keeping it 100% as-is 😌)

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cc_hash_table(It first, It last, const hash_fn & h, const eq_fn & e, const comb_hash_fn & ch) — range + three policies 🦋

template<typename Key , typename Mapped , typename Hash_Fn  = typename
    detail::default_hash_fn<Key>::type, typename Eq_Fn  = typename
    detail::default_eq_fn<Key>::type, typename Comb_Hash_Fn  =
    detail::default_comb_hash_fn::type, typename Resize_Policy  = typename
    detail::default_resize_policy<Comb_Hash_Fn>::type, bool Store_Hash =
    detail::default_store_hash, typename _Alloc  = std::allocator<char>>
template<typename It > __gnu_pbds::cc_hash_table< Key, Mapped, Hash_Fn,
Eq_Fn, Comb_Hash_Fn, Resize_Policy, Store_Hash, _Alloc >::cc_hash_table
(It first, It last, const hash_fn & h, const eq_fn & e, const
comb_hash_fn & ch) [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_hash_fn will be copied by the hash_fn object of the container object, r_eq_fn will be copied by the eq_fn object of the container object, and r_comb_hash_fn will be copied by the comb_hash_fn object of the container object. We're so back 🌟

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cc_hash_table(It first, It last, const hash_fn & h, const eq_fn & e, const comb_hash_fn & ch, const resize_policy & rp) — the everything constructor 💀👑

template<typename Key , typename Mapped , typename Hash_Fn  = typename
    detail::default_hash_fn<Key>::type, typename Eq_Fn  = typename
    detail::default_eq_fn<Key>::type, typename Comb_Hash_Fn  =
    detail::default_comb_hash_fn::type, typename Resize_Policy  = typename
    detail::default_resize_policy<Comb_Hash_Fn>::type, bool Store_Hash =
    detail::default_store_hash, typename _Alloc  = std::allocator<char>>
template<typename It > __gnu_pbds::cc_hash_table< Key, Mapped, Hash_Fn,
Eq_Fn, Comb_Hash_Fn, Resize_Policy, Store_Hash, _Alloc >::cc_hash_table
(It first, It last, const hash_fn & h, const eq_fn & e, const
comb_hash_fn & ch, const resize_policy & rp) [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_hash_fn will be copied by the hash_fn object of the container object, r_eq_fn will be copied by the eq_fn object of the container object, r_comb_hash_fn will be copied by the comb_hash_fn object of the container object, and r_resize_policy will be copied by the resize_policy object of the container object. Range plus literally every policy — the final boss of constructors, no cap 🔥

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🌸 Author 🌸

Generated automatically by Doxygen for libstdc++ from the source code. Not a human, not a group chat, just Doxygen doing its lil thing 🤖💖

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And that's a wrap on this page, bestie! 🎀 This one came from libstdc++, that adorable automatic Doxygen generation situation, and the footer of the original was the usual libstd__gnu_pbds::cc..._Hash, _Alloc >(3cxx) section marker — so yeah, that's the source, that's the version, that's the date line, all accounted for ✨ Go forth and hash, you icon 👑💅