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The C and C++ Include Header Files

/usr/include/python3.12/cpython/setobject.h


$ cat -n /usr/include/python3.12/cpython/setobject.h

     1	#ifndef Py_CPYTHON_SETOBJECT_H
     2	#  error "this header file must not be included directly"
     3	#endif
     4	
     5	/* There are three kinds of entries in the table:
     6	
     7	1. Unused:  key == NULL and hash == 0
     8	2. Dummy:   key == dummy and hash == -1
     9	3. Active:  key != NULL and key != dummy and hash != -1
    10	
    11	The hash field of Unused slots is always zero.
    12	
    13	The hash field of Dummy slots are set to -1
    14	meaning that dummy entries can be detected by
    15	either entry->key==dummy or by entry->hash==-1.
    16	*/
    17	
    18	#define PySet_MINSIZE 8
    19	
    20	typedef struct {
    21	    PyObject *key;
    22	    Py_hash_t hash;             /* Cached hash code of the key */
    23	} setentry;
    24	
    25	/* The SetObject data structure is shared by set and frozenset objects.
    26	
    27	Invariant for sets:
    28	 - hash is -1
    29	
    30	Invariants for frozensets:
    31	 - data is immutable.
    32	 - hash is the hash of the frozenset or -1 if not computed yet.
    33	
    34	*/
    35	
    36	typedef struct {
    37	    PyObject_HEAD
    38	
    39	    Py_ssize_t fill;            /* Number active and dummy entries*/
    40	    Py_ssize_t used;            /* Number active entries */
    41	
    42	    /* The table contains mask + 1 slots, and that's a power of 2.
    43	     * We store the mask instead of the size because the mask is more
    44	     * frequently needed.
    45	     */
    46	    Py_ssize_t mask;
    47	
    48	    /* The table points to a fixed-size smalltable for small tables
    49	     * or to additional malloc'ed memory for bigger tables.
    50	     * The table pointer is never NULL which saves us from repeated
    51	     * runtime null-tests.
    52	     */
    53	    setentry *table;
    54	    Py_hash_t hash;             /* Only used by frozenset objects */
    55	    Py_ssize_t finger;          /* Search finger for pop() */
    56	
    57	    setentry smalltable[PySet_MINSIZE];
    58	    PyObject *weakreflist;      /* List of weak references */
    59	} PySetObject;
    60	
    61	#define _PySet_CAST(so) \
    62	    (assert(PyAnySet_Check(so)), _Py_CAST(PySetObject*, so))
    63	
    64	static inline Py_ssize_t PySet_GET_SIZE(PyObject *so) {
    65	    return _PySet_CAST(so)->used;
    66	}
    67	#define PySet_GET_SIZE(so) PySet_GET_SIZE(_PyObject_CAST(so))
    68	
    69	PyAPI_DATA(PyObject *) _PySet_Dummy;
    70	
    71	PyAPI_FUNC(int) _PySet_NextEntry(PyObject *set, Py_ssize_t *pos, PyObject **key, Py_hash_t *hash);
    72	PyAPI_FUNC(int) _PySet_Update(PyObject *set, PyObject *iterable);