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EDITING: pycore_hamt.h

#ifndef Py_INTERNAL_HAMT_H
#define Py_INTERNAL_HAMT_H

#ifndef Py_BUILD_CORE
#  error "this header requires Py_BUILD_CORE define"
#endif

/*
HAMT tree is shaped by hashes of keys. Every group of 5 bits of a hash denotes
the exact position of the key in one level of the tree. Since we're using
32 bit hashes, we can have at most 7 such levels. Although if there are
two distinct keys with equal hashes, they will have to occupy the same
cell in the 7th level of the tree -- so we'd put them in a "collision" node.
Which brings the total possible tree depth to 8. Read more about the actual
layout of the HAMT tree in `hamt.c`.

This constant is used to define a datastucture for storing iteration state.
*/
#define _Py_HAMT_MAX_TREE_DEPTH 8

#define PyHamt_Check(o) Py_IS_TYPE(o, &_PyHamt_Type)

/* Abstract tree node. */
typedef struct {
    PyObject_HEAD
} PyHamtNode;

/* An HAMT immutable mapping collection. */
typedef struct {
    PyObject_HEAD
    PyHamtNode *h_root;
    PyObject *h_weakreflist;
    Py_ssize_t h_count;
} PyHamtObject;

/* A struct to hold the state of depth-first traverse of the tree.

HAMT is an immutable collection.  Iterators will hold a strong reference
   to it, and every node in the HAMT has strong references to its children.

So for iterators, we can implement zero allocations and zero reference
   inc/dec depth-first iteration.

- i_nodes: an array of seven pointers to tree nodes
   - i_level: the current node in i_nodes
   - i_pos: an array of positions within nodes in i_nodes.
*/
typedef struct {
    PyHamtNode *i_nodes[_Py_HAMT_MAX_TREE_DEPTH];
    Py_ssize_t i_pos[_Py_HAMT_MAX_TREE_DEPTH];
    int8_t i_level;
} PyHamtIteratorState;

/* Base iterator object.

Contains the iteration state, a pointer to the HAMT tree,
   and a pointer to the 'yield function'.  The latter is a simple
   function that returns a key/value tuple for the 'Items' iterator,
   just a key for the 'Keys' iterator, and a value for the 'Values'
   iterator.
*/
typedef struct {
    PyObject_HEAD
    PyHamtObject *hi_obj;
    PyHamtIteratorState hi_iter;
    binaryfunc hi_yield;
} PyHamtIterator;

PyAPI_DATA(PyTypeObject) _PyHamt_Type;
PyAPI_DATA(PyTypeObject) _PyHamt_ArrayNode_Type;
PyAPI_DATA(PyTypeObject) _PyHamt_BitmapNode_Type;
PyAPI_DATA(PyTypeObject) _PyHamt_CollisionNode_Type;
PyAPI_DATA(PyTypeObject) _PyHamtKeys_Type;
PyAPI_DATA(PyTypeObject) _PyHamtValues_Type;
PyAPI_DATA(PyTypeObject) _PyHamtItems_Type;

/* Create a new HAMT immutable mapping. */
PyHamtObject * _PyHamt_New(void);

/* Return a new collection based on "o", but with an additional
   key/val pair. */
PyHamtObject * _PyHamt_Assoc(PyHamtObject *o, PyObject *key, PyObject *val);

/* Return a new collection based on "o", but without "key". */
PyHamtObject * _PyHamt_Without(PyHamtObject *o, PyObject *key);

/* Find "key" in the "o" collection.

Return:
   - -1: An error occurred.
   - 0: "key" wasn't found in "o".
   - 1: "key" is in "o"; "*val" is set to its value (a borrowed ref).
*/
int _PyHamt_Find(PyHamtObject *o, PyObject *key, PyObject **val);

/* Check if "v" is equal to "w".

Return:
   - 0: v != w
   - 1: v == w
   - -1: An error occurred.
*/
int _PyHamt_Eq(PyHamtObject *v, PyHamtObject *w);

/* Return the size of "o"; equivalent of "len(o)". */
Py_ssize_t _PyHamt_Len(PyHamtObject *o);

/* Return a Keys iterator over "o". */
PyObject * _PyHamt_NewIterKeys(PyHamtObject *o);

/* Return a Values iterator over "o". */
PyObject * _PyHamt_NewIterValues(PyHamtObject *o);

/* Return a Items iterator over "o". */
PyObject * _PyHamt_NewIterItems(PyHamtObject *o);

int _PyHamt_Init(void);
void _PyHamt_Fini(void);

#endif /* !Py_INTERNAL_HAMT_H */

CANCEL

Name	Type	Size	Modified	Actions
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📄 pegen_interface.h	H	953 B	2025-10-31 18:40	EDIT
📄 pycore_abstract.h	H	479 B	2025-10-31 18:40	EDIT
📄 pycore_accu.h	H	1.1 KB	2025-10-31 18:40	EDIT
📄 pycore_atomic.h	H	16.6 KB	2025-10-31 18:40	EDIT
📄 pycore_bytes_methods.h	H	3.3 KB	2025-10-31 18:40	EDIT
📄 pycore_byteswap.h	H	2.6 KB	2025-10-31 18:40	EDIT
📄 pycore_call.h	H	870 B	2025-10-31 18:40	EDIT
📄 pycore_ceval.h	H	3.3 KB	2025-10-31 18:40	EDIT
📄 pycore_code.h	H	541 B	2025-10-31 18:40	EDIT
📄 pycore_condvar.h	H	2.7 KB	2025-10-31 18:40	EDIT
📄 pycore_context.h	H	800 B	2025-10-31 18:40	EDIT
📄 pycore_dtoa.h	H	646 B	2025-10-31 18:40	EDIT
📄 pycore_fileutils.h	H	1.5 KB	2025-10-31 18:40	EDIT
📄 pycore_gc.h	H	6.5 KB	2025-10-31 18:40	EDIT
📄 pycore_getopt.h	H	490 B	2025-10-31 18:40	EDIT
📄 pycore_gil.h	H	1.5 KB	2025-10-31 18:40	EDIT
📄 pycore_hamt.h	H	3.6 KB	2025-10-31 18:40	EDIT
📄 pycore_hashtable.h	H	4.1 KB	2025-10-31 18:40	EDIT
📄 pycore_import.h	H	473 B	2025-10-31 18:40	EDIT
📄 pycore_initconfig.h	H	5.1 KB	2025-10-31 18:40	EDIT
📄 pycore_interp.h	H	5.2 KB	2025-10-31 18:40	EDIT
📄 pycore_long.h	H	1.5 KB	2025-10-31 18:40	EDIT
📄 pycore_object.h	H	4.1 KB	2025-10-31 18:40	EDIT
📄 pycore_pathconfig.h	H	1.9 KB	2025-10-31 18:40	EDIT
📄 pycore_pyerrors.h	H	2 KB	2025-10-31 18:40	EDIT
📄 pycore_pyhash.h	H	206 B	2025-10-31 18:40	EDIT
📄 pycore_pylifecycle.h	H	3.7 KB	2025-10-31 18:40	EDIT
📄 pycore_pymem.h	H	3.3 KB	2025-10-31 18:40	EDIT
📄 pycore_pystate.h	H	3.5 KB	2025-10-31 18:40	EDIT
📄 pycore_runtime.h	H	4.3 KB	2025-10-31 18:40	EDIT
📄 pycore_sysmodule.h	H	548 B	2025-10-31 18:40	EDIT
📄 pycore_traceback.h	H	3 KB	2025-10-31 18:40	EDIT
📄 pycore_tupleobject.h	H	442 B	2025-10-31 18:40	EDIT
📄 pycore_warnings.h	H	633 B	2025-10-31 18:40	EDIT