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The C and C++ Include Header Files

cat -n /usr/include/python3.14/internal/pycore_hamt.h

     1	#ifndef Py_INTERNAL_HAMT_H
     2	#define Py_INTERNAL_HAMT_H
     3	
     4	#ifndef Py_BUILD_CORE
     5	#  error "this header requires Py_BUILD_CORE define"
     6	#endif
     7	
     8	#include "pycore_structs.h"       // PyHamtNode
     9	
    10	/*
    11	HAMT tree is shaped by hashes of keys. Every group of 5 bits of a hash denotes
    12	the exact position of the key in one level of the tree. Since we're using
    13	32 bit hashes, we can have at most 7 such levels. Although if there are
    14	two distinct keys with equal hashes, they will have to occupy the same
    15	cell in the 7th level of the tree -- so we'd put them in a "collision" node.
    16	Which brings the total possible tree depth to 8. Read more about the actual
    17	layout of the HAMT tree in `hamt.c`.
    18	
    19	This constant is used to define a datastucture for storing iteration state.
    20	*/
    21	#define _Py_HAMT_MAX_TREE_DEPTH 8
    22	
    23	
    24	extern PyTypeObject _PyHamt_Type;
    25	extern PyTypeObject _PyHamt_ArrayNode_Type;
    26	extern PyTypeObject _PyHamt_BitmapNode_Type;
    27	extern PyTypeObject _PyHamt_CollisionNode_Type;
    28	extern PyTypeObject _PyHamtKeys_Type;
    29	extern PyTypeObject _PyHamtValues_Type;
    30	extern PyTypeObject _PyHamtItems_Type;
    31	
    32	
    33	/* other API */
    34	
    35	#define PyHamt_Check(o) Py_IS_TYPE((o), &_PyHamt_Type)
    36	
    37	
    38	/* A struct to hold the state of depth-first traverse of the tree.
    39	
    40	   HAMT is an immutable collection.  Iterators will hold a strong reference
    41	   to it, and every node in the HAMT has strong references to its children.
    42	
    43	   So for iterators, we can implement zero allocations and zero reference
    44	   inc/dec depth-first iteration.
    45	
    46	   - i_nodes: an array of seven pointers to tree nodes
    47	   - i_level: the current node in i_nodes
    48	   - i_pos: an array of positions within nodes in i_nodes.
    49	*/
    50	typedef struct {
    51	    PyHamtNode *i_nodes[_Py_HAMT_MAX_TREE_DEPTH];
    52	    Py_ssize_t i_pos[_Py_HAMT_MAX_TREE_DEPTH];
    53	    int8_t i_level;
    54	} PyHamtIteratorState;
    55	
    56	
    57	/* Base iterator object.
    58	
    59	   Contains the iteration state, a pointer to the HAMT tree,
    60	   and a pointer to the 'yield function'.  The latter is a simple
    61	   function that returns a key/value tuple for the 'Items' iterator,
    62	   just a key for the 'Keys' iterator, and a value for the 'Values'
    63	   iterator.
    64	*/
    65	typedef struct {
    66	    PyObject_HEAD
    67	    PyHamtObject *hi_obj;
    68	    PyHamtIteratorState hi_iter;
    69	    binaryfunc hi_yield;
    70	} PyHamtIterator;
    71	
    72	
    73	/* Create a new HAMT immutable mapping. */
    74	PyHamtObject * _PyHamt_New(void);
    75	
    76	/* Return a new collection based on "o", but with an additional
    77	   key/val pair. */
    78	PyHamtObject * _PyHamt_Assoc(PyHamtObject *o, PyObject *key, PyObject *val);
    79	
    80	/* Return a new collection based on "o", but without "key". */
    81	PyHamtObject * _PyHamt_Without(PyHamtObject *o, PyObject *key);
    82	
    83	/* Find "key" in the "o" collection.
    84	
    85	   Return:
    86	   - -1: An error occurred.
    87	   - 0: "key" wasn't found in "o".
    88	   - 1: "key" is in "o"; "*val" is set to its value (a borrowed ref).
    89	*/
    90	int _PyHamt_Find(PyHamtObject *o, PyObject *key, PyObject **val);
    91	
    92	/* Check if "v" is equal to "w".
    93	
    94	   Return:
    95	   - 0: v != w
    96	   - 1: v == w
    97	   - -1: An error occurred.
    98	*/
    99	int _PyHamt_Eq(PyHamtObject *v, PyHamtObject *w);
   100	
   101	/* Return the size of "o"; equivalent of "len(o)". */
   102	Py_ssize_t _PyHamt_Len(PyHamtObject *o);
   103	
   104	/* Return a Keys iterator over "o". */
   105	PyObject * _PyHamt_NewIterKeys(PyHamtObject *o);
   106	
   107	/* Return a Values iterator over "o". */
   108	PyObject * _PyHamt_NewIterValues(PyHamtObject *o);
   109	
   110	/* Return a Items iterator over "o". */
   111	PyObject * _PyHamt_NewIterItems(PyHamtObject *o);
   112	
   113	#endif /* !Py_INTERNAL_HAMT_H */