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The C and C++ Include Header Files

/usr/include/python3.10/internal/pycore_hamt.h


$ cat -n /usr/include/python3.10/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	
     9	/*
    10	HAMT tree is shaped by hashes of keys. Every group of 5 bits of a hash denotes
    11	the exact position of the key in one level of the tree. Since we're using
    12	32 bit hashes, we can have at most 7 such levels. Although if there are
    13	two distinct keys with equal hashes, they will have to occupy the same
    14	cell in the 7th level of the tree -- so we'd put them in a "collision" node.
    15	Which brings the total possible tree depth to 8. Read more about the actual
    16	layout of the HAMT tree in `hamt.c`.
    17	
    18	This constant is used to define a datastucture for storing iteration state.
    19	*/
    20	#define _Py_HAMT_MAX_TREE_DEPTH 8
    21	
    22	
    23	#define PyHamt_Check(o) Py_IS_TYPE(o, &_PyHamt_Type)
    24	
    25	
    26	/* Abstract tree node. */
    27	typedef struct {
    28	    PyObject_HEAD
    29	} PyHamtNode;
    30	
    31	
    32	/* An HAMT immutable mapping collection. */
    33	typedef struct {
    34	    PyObject_HEAD
    35	    PyHamtNode *h_root;
    36	    PyObject *h_weakreflist;
    37	    Py_ssize_t h_count;
    38	} PyHamtObject;
    39	
    40	
    41	/* A struct to hold the state of depth-first traverse of the tree.
    42	
    43	   HAMT is an immutable collection.  Iterators will hold a strong reference
    44	   to it, and every node in the HAMT has strong references to its children.
    45	
    46	   So for iterators, we can implement zero allocations and zero reference
    47	   inc/dec depth-first iteration.
    48	
    49	   - i_nodes: an array of seven pointers to tree nodes
    50	   - i_level: the current node in i_nodes
    51	   - i_pos: an array of positions within nodes in i_nodes.
    52	*/
    53	typedef struct {
    54	    PyHamtNode *i_nodes[_Py_HAMT_MAX_TREE_DEPTH];
    55	    Py_ssize_t i_pos[_Py_HAMT_MAX_TREE_DEPTH];
    56	    int8_t i_level;
    57	} PyHamtIteratorState;
    58	
    59	
    60	/* Base iterator object.
    61	
    62	   Contains the iteration state, a pointer to the HAMT tree,
    63	   and a pointer to the 'yield function'.  The latter is a simple
    64	   function that returns a key/value tuple for the 'Items' iterator,
    65	   just a key for the 'Keys' iterator, and a value for the 'Values'
    66	   iterator.
    67	*/
    68	typedef struct {
    69	    PyObject_HEAD
    70	    PyHamtObject *hi_obj;
    71	    PyHamtIteratorState hi_iter;
    72	    binaryfunc hi_yield;
    73	} PyHamtIterator;
    74	
    75	
    76	PyAPI_DATA(PyTypeObject) _PyHamt_Type;
    77	PyAPI_DATA(PyTypeObject) _PyHamt_ArrayNode_Type;
    78	PyAPI_DATA(PyTypeObject) _PyHamt_BitmapNode_Type;
    79	PyAPI_DATA(PyTypeObject) _PyHamt_CollisionNode_Type;
    80	PyAPI_DATA(PyTypeObject) _PyHamtKeys_Type;
    81	PyAPI_DATA(PyTypeObject) _PyHamtValues_Type;
    82	PyAPI_DATA(PyTypeObject) _PyHamtItems_Type;
    83	
    84	
    85	/* Create a new HAMT immutable mapping. */
    86	PyHamtObject * _PyHamt_New(void);
    87	
    88	/* Return a new collection based on "o", but with an additional
    89	   key/val pair. */
    90	PyHamtObject * _PyHamt_Assoc(PyHamtObject *o, PyObject *key, PyObject *val);
    91	
    92	/* Return a new collection based on "o", but without "key". */
    93	PyHamtObject * _PyHamt_Without(PyHamtObject *o, PyObject *key);
    94	
    95	/* Find "key" in the "o" collection.
    96	
    97	   Return:
    98	   - -1: An error occurred.
    99	   - 0: "key" wasn't found in "o".
   100	   - 1: "key" is in "o"; "*val" is set to its value (a borrowed ref).
   101	*/
   102	int _PyHamt_Find(PyHamtObject *o, PyObject *key, PyObject **val);
   103	
   104	/* Check if "v" is equal to "w".
   105	
   106	   Return:
   107	   - 0: v != w
   108	   - 1: v == w
   109	   - -1: An error occurred.
   110	*/
   111	int _PyHamt_Eq(PyHamtObject *v, PyHamtObject *w);
   112	
   113	/* Return the size of "o"; equivalent of "len(o)". */
   114	Py_ssize_t _PyHamt_Len(PyHamtObject *o);
   115	
   116	/* Return a Keys iterator over "o". */
   117	PyObject * _PyHamt_NewIterKeys(PyHamtObject *o);
   118	
   119	/* Return a Values iterator over "o". */
   120	PyObject * _PyHamt_NewIterValues(PyHamtObject *o);
   121	
   122	/* Return a Items iterator over "o". */
   123	PyObject * _PyHamt_NewIterItems(PyHamtObject *o);
   124	
   125	int _PyHamt_Init(void);
   126	void _PyHamt_Fini(void);
   127	
   128	#endif /* !Py_INTERNAL_HAMT_H */