3 * Copyright (C) 1991, 1992, 1993, 1996, 1997, 1998, 1999,
4 * 2000, 2001, 2002, 2003, 2005, 2006, 2007, 2008, by Larry Wall and others
6 * You may distribute under the terms of either the GNU General Public
7 * License or the Artistic License, as specified in the README file.
11 /* entry in hash value chain */
13 /* Keep hent_next first in this structure, because sv_free_arenas take
14 advantage of this to share code between the he arenas and the SV
16 HE *hent_next; /* next entry in chain */
17 HEK *hent_hek; /* hash key */
19 SV *hent_val; /* scalar value that was hashed */
20 Size_t hent_refcount; /* references for this shared hash key */
24 /* hash key -- defined separately for use as shared pointer */
26 U32 hek_hash; /* hash of key */
27 I32 hek_len; /* length of hash key */
28 char hek_key[1]; /* variable-length hash key */
29 /* the hash-key is \0-terminated */
30 /* after the \0 there is a byte for flags, such as whether the key
35 struct he shared_he_he;
36 struct hek shared_he_hek;
40 Don't access this directly.
41 Use the funcs in mro.c
45 /* structure may change, so not public yet */
49 /* repurposed as a hash holding the different MROs private data. */
50 AV *mro_linear_dfs; /* cached dfs @ISA linearization */
51 /* repurposed as a pointer directly to the current MROs private data. */
52 AV *mro_linear_c3; /* cached c3 @ISA linearization */
53 HV *mro_nextmethod; /* next::method caching */
54 U32 cache_gen; /* Bumping this invalidates our method cache */
55 U32 pkg_gen; /* Bumps when local methods/@ISA change */
56 const struct mro_alg *mro_which; /* which mro alg is in use? */
57 HV *isa; /* Everything this class @ISA */
61 Don't access this directly.
65 HEK *xhv_name; /* name, if a symbol table */
66 AV *xhv_backreferences; /* back references for weak references */
67 HE *xhv_eiter; /* current entry of iterator */
68 I32 xhv_riter; /* current root of iterator */
69 struct mro_meta *xhv_mro_meta;
72 #define _XPVHV_ALLOCATED_HEAD \
73 STRLEN xhv_fill; /* how full xhv_array currently is */ \
74 STRLEN xhv_max /* subscript of last element of xhv_array */
81 /* This structure must match the beginning of struct xpvmg in sv.h. */
87 #define xhv_keys xiv_u.xivu_iv
90 _XPVHV_ALLOCATED_HEAD;
94 #undef _XPVHV_ALLOCATED_HEAD
98 /* FYI: This is the "One-at-a-Time" algorithm by Bob Jenkins
99 * from requirements by Colin Plumb.
100 * (http://burtleburtle.net/bob/hash/doobs.html) */
101 /* The use of a temporary pointer and the casting games
102 * is needed to serve the dual purposes of
103 * (a) the hashed data being interpreted as "unsigned char" (new since 5.8,
104 * a "char" can be either signed or unsigned, depending on the compiler)
105 * (b) catering for old code that uses a "char"
107 * The "hash seed" feature was added in Perl 5.8.1 to perturb the results
108 * to avoid "algorithmic complexity attacks".
110 * If USE_HASH_SEED is defined, hash randomisation is done by default
111 * If USE_HASH_SEED_EXPLICIT is defined, hash randomisation is done
112 * only if the environment variable PERL_HASH_SEED is set.
113 * For maximal control, one can define PERL_HASH_SEED.
114 * (see also perl.c:perl_parse()).
116 #ifndef PERL_HASH_SEED
117 # if defined(USE_HASH_SEED) || defined(USE_HASH_SEED_EXPLICIT)
118 # define PERL_HASH_SEED PL_hash_seed
120 # define PERL_HASH_SEED 0
123 #define PERL_HASH(hash,str,len) \
125 register const char * const s_PeRlHaSh_tmp = str; \
126 register const unsigned char *s_PeRlHaSh = (const unsigned char *)s_PeRlHaSh_tmp; \
127 register I32 i_PeRlHaSh = len; \
128 register U32 hash_PeRlHaSh = PERL_HASH_SEED; \
129 while (i_PeRlHaSh--) { \
130 hash_PeRlHaSh += *s_PeRlHaSh++; \
131 hash_PeRlHaSh += (hash_PeRlHaSh << 10); \
132 hash_PeRlHaSh ^= (hash_PeRlHaSh >> 6); \
134 hash_PeRlHaSh += (hash_PeRlHaSh << 3); \
135 hash_PeRlHaSh ^= (hash_PeRlHaSh >> 11); \
136 (hash) = (hash_PeRlHaSh + (hash_PeRlHaSh << 15)); \
139 /* Only hv.c and mod_perl should be doing this. */
140 #ifdef PERL_HASH_INTERNAL_ACCESS
141 #define PERL_HASH_INTERNAL(hash,str,len) \
143 register const char * const s_PeRlHaSh_tmp = str; \
144 register const unsigned char *s_PeRlHaSh = (const unsigned char *)s_PeRlHaSh_tmp; \
145 register I32 i_PeRlHaSh = len; \
146 register U32 hash_PeRlHaSh = PL_rehash_seed; \
147 while (i_PeRlHaSh--) { \
148 hash_PeRlHaSh += *s_PeRlHaSh++; \
149 hash_PeRlHaSh += (hash_PeRlHaSh << 10); \
150 hash_PeRlHaSh ^= (hash_PeRlHaSh >> 6); \
152 hash_PeRlHaSh += (hash_PeRlHaSh << 3); \
153 hash_PeRlHaSh ^= (hash_PeRlHaSh >> 11); \
154 (hash) = (hash_PeRlHaSh + (hash_PeRlHaSh << 15)); \
159 =head1 Hash Manipulation Functions
161 =for apidoc AmU||HEf_SVKEY
162 This flag, used in the length slot of hash entries and magic structures,
163 specifies the structure contains an C<SV*> pointer where a C<char*> pointer
164 is to be expected. (For information only--not to be used).
168 =for apidoc AmU||Nullhv
171 (deprecated - use C<(HV *)NULL> instead)
173 =head1 Hash Manipulation Functions
175 =for apidoc Am|char*|HvNAME|HV* stash
176 Returns the package name of a stash, or NULL if C<stash> isn't a stash.
177 See C<SvSTASH>, C<CvSTASH>.
179 =for apidoc Am|void*|HeKEY|HE* he
180 Returns the actual pointer stored in the key slot of the hash entry. The
181 pointer may be either C<char*> or C<SV*>, depending on the value of
182 C<HeKLEN()>. Can be assigned to. The C<HePV()> or C<HeSVKEY()> macros are
183 usually preferable for finding the value of a key.
185 =for apidoc Am|STRLEN|HeKLEN|HE* he
186 If this is negative, and amounts to C<HEf_SVKEY>, it indicates the entry
187 holds an C<SV*> key. Otherwise, holds the actual length of the key. Can
188 be assigned to. The C<HePV()> macro is usually preferable for finding key
191 =for apidoc Am|SV*|HeVAL|HE* he
192 Returns the value slot (type C<SV*>) stored in the hash entry.
194 =for apidoc Am|U32|HeHASH|HE* he
195 Returns the computed hash stored in the hash entry.
197 =for apidoc Am|char*|HePV|HE* he|STRLEN len
198 Returns the key slot of the hash entry as a C<char*> value, doing any
199 necessary dereferencing of possibly C<SV*> keys. The length of the string
200 is placed in C<len> (this is a macro, so do I<not> use C<&len>). If you do
201 not care about what the length of the key is, you may use the global
202 variable C<PL_na>, though this is rather less efficient than using a local
203 variable. Remember though, that hash keys in perl are free to contain
204 embedded nulls, so using C<strlen()> or similar is not a good way to find
205 the length of hash keys. This is very similar to the C<SvPV()> macro
206 described elsewhere in this document. See also C<HeUTF8>.
208 If you are using C<HePV> to get values to pass to C<newSVpvn()> to create a
209 new SV, you should consider using C<newSVhek(HeKEY_hek(he))> as it is more
212 =for apidoc Am|char*|HeUTF8|HE* he|STRLEN len
213 Returns whether the C<char *> value returned by C<HePV> is encoded in UTF-8,
214 doing any necessary dereferencing of possibly C<SV*> keys. The value returned
215 will be 0 or non-0, not necessarily 1 (or even a value with any low bits set),
216 so B<do not> blindly assign this to a C<bool> variable, as C<bool> may be a
219 =for apidoc Am|SV*|HeSVKEY|HE* he
220 Returns the key as an C<SV*>, or C<NULL> if the hash entry does not
221 contain an C<SV*> key.
223 =for apidoc Am|SV*|HeSVKEY_force|HE* he
224 Returns the key as an C<SV*>. Will create and return a temporary mortal
225 C<SV*> if the hash entry contains only a C<char*> key.
227 =for apidoc Am|SV*|HeSVKEY_set|HE* he|SV* sv
228 Sets the key to a given C<SV*>, taking care to set the appropriate flags to
229 indicate the presence of an C<SV*> key, and returns the same
235 /* these hash entry flags ride on hent_klen (for use only in magic/tied HVs) */
236 #define HEf_SVKEY -2 /* hent_key is an SV* */
239 # define Nullhv Null(HV*)
241 #define HvARRAY(hv) ((hv)->sv_u.svu_hash)
242 #define HvFILL(hv) ((XPVHV*) SvANY(hv))->xhv_fill
243 #define HvMAX(hv) ((XPVHV*) SvANY(hv))->xhv_max
244 /* This quite intentionally does no flag checking first. That's your
246 #define HvAUX(hv) ((struct xpvhv_aux*)&(HvARRAY(hv)[HvMAX(hv)+1]))
247 #define HvRITER(hv) (*Perl_hv_riter_p(aTHX_ MUTABLE_HV(hv)))
248 #define HvEITER(hv) (*Perl_hv_eiter_p(aTHX_ MUTABLE_HV(hv)))
249 #define HvRITER_set(hv,r) Perl_hv_riter_set(aTHX_ MUTABLE_HV(hv), r)
250 #define HvEITER_set(hv,e) Perl_hv_eiter_set(aTHX_ MUTABLE_HV(hv), e)
251 #define HvRITER_get(hv) (SvOOK(hv) ? HvAUX(hv)->xhv_riter : -1)
252 #define HvEITER_get(hv) (SvOOK(hv) ? HvAUX(hv)->xhv_eiter : NULL)
253 #define HvNAME(hv) HvNAME_get(hv)
255 /* Checking that hv is a valid package stash is the
256 caller's responsibility */
257 #define HvMROMETA(hv) (HvAUX(hv)->xhv_mro_meta \
258 ? HvAUX(hv)->xhv_mro_meta \
261 /* FIXME - all of these should use a UTF8 aware API, which should also involve
262 getting the length. */
263 /* This macro may go away without notice. */
264 #define HvNAME_HEK(hv) (SvOOK(hv) ? HvAUX(hv)->xhv_name : NULL)
265 #define HvNAME_get(hv) ((SvOOK(hv) && (HvAUX(hv)->xhv_name)) \
266 ? HEK_KEY(HvAUX(hv)->xhv_name) : NULL)
267 #define HvNAMELEN_get(hv) ((SvOOK(hv) && (HvAUX(hv)->xhv_name)) \
268 ? HEK_LEN(HvAUX(hv)->xhv_name) : 0)
270 /* the number of keys (including any placeholers) */
271 #define XHvTOTALKEYS(xhv) ((xhv)->xhv_keys)
274 * HvKEYS gets the number of keys that actually exist(), and is provided
275 * for backwards compatibility with old XS code. The core uses HvUSEDKEYS
276 * (keys, excluding placeholdes) and HvTOTALKEYS (including placeholders)
278 #define HvKEYS(hv) HvUSEDKEYS(hv)
279 #define HvUSEDKEYS(hv) (HvTOTALKEYS(hv) - HvPLACEHOLDERS_get(hv))
280 #define HvTOTALKEYS(hv) XHvTOTALKEYS((XPVHV*) SvANY(hv))
281 #define HvPLACEHOLDERS(hv) (*Perl_hv_placeholders_p(aTHX_ MUTABLE_HV(hv)))
282 #define HvPLACEHOLDERS_get(hv) (SvMAGIC(hv) ? Perl_hv_placeholders_get(aTHX_ (const HV *)hv) : 0)
283 #define HvPLACEHOLDERS_set(hv,p) Perl_hv_placeholders_set(aTHX_ MUTABLE_HV(hv), p)
285 #define HvSHAREKEYS(hv) (SvFLAGS(hv) & SVphv_SHAREKEYS)
286 #define HvSHAREKEYS_on(hv) (SvFLAGS(hv) |= SVphv_SHAREKEYS)
287 #define HvSHAREKEYS_off(hv) (SvFLAGS(hv) &= ~SVphv_SHAREKEYS)
289 /* This is an optimisation flag. It won't be set if all hash keys have a 0
290 * flag. Currently the only flags relate to utf8.
291 * Hence it won't be set if all keys are 8 bit only. It will be set if any key
292 * is utf8 (including 8 bit keys that were entered as utf8, and need upgrading
293 * when retrieved during iteration. It may still be set when there are no longer
295 * See HVhek_ENABLEHVKFLAGS for the trigger.
297 #define HvHASKFLAGS(hv) (SvFLAGS(hv) & SVphv_HASKFLAGS)
298 #define HvHASKFLAGS_on(hv) (SvFLAGS(hv) |= SVphv_HASKFLAGS)
299 #define HvHASKFLAGS_off(hv) (SvFLAGS(hv) &= ~SVphv_HASKFLAGS)
301 #define HvLAZYDEL(hv) (SvFLAGS(hv) & SVphv_LAZYDEL)
302 #define HvLAZYDEL_on(hv) (SvFLAGS(hv) |= SVphv_LAZYDEL)
303 #define HvLAZYDEL_off(hv) (SvFLAGS(hv) &= ~SVphv_LAZYDEL)
305 #define HvREHASH(hv) (SvFLAGS(hv) & SVphv_REHASH)
306 #define HvREHASH_on(hv) (SvFLAGS(hv) |= SVphv_REHASH)
307 #define HvREHASH_off(hv) (SvFLAGS(hv) &= ~SVphv_REHASH)
310 # define Nullhe Null(HE*)
312 #define HeNEXT(he) (he)->hent_next
313 #define HeKEY_hek(he) (he)->hent_hek
314 #define HeKEY(he) HEK_KEY(HeKEY_hek(he))
315 #define HeKEY_sv(he) (*(SV**)HeKEY(he))
316 #define HeKLEN(he) HEK_LEN(HeKEY_hek(he))
317 #define HeKUTF8(he) HEK_UTF8(HeKEY_hek(he))
318 #define HeKWASUTF8(he) HEK_WASUTF8(HeKEY_hek(he))
319 #define HeKREHASH(he) HEK_REHASH(HeKEY_hek(he))
320 #define HeKLEN_UTF8(he) (HeKUTF8(he) ? -HeKLEN(he) : HeKLEN(he))
321 #define HeKFLAGS(he) HEK_FLAGS(HeKEY_hek(he))
322 #define HeVAL(he) (he)->he_valu.hent_val
323 #define HeHASH(he) HEK_HASH(HeKEY_hek(he))
324 #define HePV(he,lp) ((HeKLEN(he) == HEf_SVKEY) ? \
325 SvPV(HeKEY_sv(he),lp) : \
326 ((lp = HeKLEN(he)), HeKEY(he)))
327 #define HeUTF8(he) ((HeKLEN(he) == HEf_SVKEY) ? \
328 SvUTF8(HeKEY_sv(he)) : \
331 #define HeSVKEY(he) ((HeKEY(he) && \
332 HeKLEN(he) == HEf_SVKEY) ? \
335 #define HeSVKEY_force(he) (HeKEY(he) ? \
336 ((HeKLEN(he) == HEf_SVKEY) ? \
338 newSVpvn_flags(HeKEY(he), \
339 HeKLEN(he), SVs_TEMP)) : \
341 #define HeSVKEY_set(he,sv) ((HeKLEN(he) = HEf_SVKEY), (HeKEY_sv(he) = sv))
344 # define Nullhek Null(HEK*)
346 #define HEK_BASESIZE STRUCT_OFFSET(HEK, hek_key[0])
347 #define HEK_HASH(hek) (hek)->hek_hash
348 #define HEK_LEN(hek) (hek)->hek_len
349 #define HEK_KEY(hek) (hek)->hek_key
350 #define HEK_FLAGS(hek) (*((unsigned char *)(HEK_KEY(hek))+HEK_LEN(hek)+1))
352 #define HVhek_UTF8 0x01 /* Key is utf8 encoded. */
353 #define HVhek_WASUTF8 0x02 /* Key is bytes here, but was supplied as utf8. */
354 #define HVhek_REHASH 0x04 /* This key is in an hv using a custom HASH . */
355 #define HVhek_UNSHARED 0x08 /* This key isn't a shared hash key. */
356 #define HVhek_FREEKEY 0x100 /* Internal flag to say key is malloc()ed. */
357 #define HVhek_PLACEHOLD 0x200 /* Internal flag to create placeholder.
358 * (may change, but Storable is a core module) */
359 #define HVhek_MASK 0xFF
361 /* Which flags enable HvHASKFLAGS? Somewhat a hack on a hack, as
362 HVhek_REHASH is only needed because the rehash flag has to be duplicated
363 into all keys as hv_iternext has no access to the hash flags. At this
364 point Storable's tests get upset, because sometimes hashes are "keyed"
365 and sometimes not, depending on the order of data insertion, and whether
366 it triggered rehashing. So currently HVhek_REHASH is exempt.
370 #define HVhek_ENABLEHVKFLAGS (HVhek_MASK & ~(HVhek_REHASH|HVhek_UNSHARED))
372 #define HEK_UTF8(hek) (HEK_FLAGS(hek) & HVhek_UTF8)
373 #define HEK_UTF8_on(hek) (HEK_FLAGS(hek) |= HVhek_UTF8)
374 #define HEK_UTF8_off(hek) (HEK_FLAGS(hek) &= ~HVhek_UTF8)
375 #define HEK_WASUTF8(hek) (HEK_FLAGS(hek) & HVhek_WASUTF8)
376 #define HEK_WASUTF8_on(hek) (HEK_FLAGS(hek) |= HVhek_WASUTF8)
377 #define HEK_WASUTF8_off(hek) (HEK_FLAGS(hek) &= ~HVhek_WASUTF8)
378 #define HEK_REHASH(hek) (HEK_FLAGS(hek) & HVhek_REHASH)
379 #define HEK_REHASH_on(hek) (HEK_FLAGS(hek) |= HVhek_REHASH)
381 /* calculate HV array allocation */
382 #ifndef PERL_USE_LARGE_HV_ALLOC
383 /* Default to allocating the correct size - default to assuming that malloc()
384 is not broken and is efficient at allocating blocks sized at powers-of-two.
386 # define PERL_HV_ARRAY_ALLOC_BYTES(size) ((size) * sizeof(HE*))
388 # define MALLOC_OVERHEAD 16
389 # define PERL_HV_ARRAY_ALLOC_BYTES(size) \
391 ? (size) * sizeof(HE*) \
392 : (size) * sizeof(HE*) * 2 - MALLOC_OVERHEAD)
395 /* Flags for hv_iternext_flags. */
396 #define HV_ITERNEXT_WANTPLACEHOLDERS 0x01 /* Don't skip placeholders. */
398 #define hv_iternext(hv) hv_iternext_flags(hv, 0)
399 #define hv_magic(hv, gv, how) sv_magic(MUTABLE_SV(hv), MUTABLE_SV(gv), how, NULL, 0)
401 /* available as a function in hv.c */
402 #define Perl_sharepvn(sv, len, hash) HEK_KEY(share_hek(sv, len, hash))
403 #define sharepvn(sv, len, hash) Perl_sharepvn(sv, len, hash)
405 #define share_hek_hek(hek) \
406 (++(((struct shared_he *)(((char *)hek) \
407 - STRUCT_OFFSET(struct shared_he, \
409 ->shared_he_he.he_valu.hent_refcount), \
412 #define hv_store_ent(hv, keysv, val, hash) \
413 ((HE *) hv_common((hv), (keysv), NULL, 0, 0, HV_FETCH_ISSTORE, \
416 #define hv_exists_ent(hv, keysv, hash) \
417 (hv_common((hv), (keysv), NULL, 0, 0, HV_FETCH_ISEXISTS, 0, (hash)) \
419 #define hv_fetch_ent(hv, keysv, lval, hash) \
420 ((HE *) hv_common((hv), (keysv), NULL, 0, 0, \
421 ((lval) ? HV_FETCH_LVALUE : 0), NULL, (hash)))
422 #define hv_delete_ent(hv, key, flags, hash) \
423 (MUTABLE_SV(hv_common((hv), (key), NULL, 0, 0, (flags) | HV_DELETE, \
426 #define hv_store_flags(hv, key, klen, val, hash, flags) \
427 ((SV**) hv_common((hv), NULL, (key), (klen), (flags), \
428 (HV_FETCH_ISSTORE|HV_FETCH_JUST_SV), (val), \
431 #define hv_store(hv, key, klen, val, hash) \
432 ((SV**) hv_common_key_len((hv), (key), (klen), \
433 (HV_FETCH_ISSTORE|HV_FETCH_JUST_SV), \
436 #define hv_exists(hv, key, klen) \
437 (hv_common_key_len((hv), (key), (klen), HV_FETCH_ISEXISTS, NULL, 0) \
440 #define hv_fetch(hv, key, klen, lval) \
441 ((SV**) hv_common_key_len((hv), (key), (klen), (lval) \
442 ? (HV_FETCH_JUST_SV | HV_FETCH_LVALUE) \
443 : HV_FETCH_JUST_SV, NULL, 0))
445 #define hv_delete(hv, key, klen, flags) \
446 (MUTABLE_SV(hv_common_key_len((hv), (key), (klen), \
447 (flags) | HV_DELETE, NULL, 0)))
449 /* This refcounted he structure is used for storing the hints used for lexical
450 pragmas. Without threads, it's basically struct he + refcount.
451 With threads, life gets more complex as the structure needs to be shared
452 between threads (because it hangs from OPs, which are shared), hence the
453 alternate definition and mutex. */
455 struct refcounted_he;
459 /* Gosh. This really isn't a good name any longer. */
460 struct refcounted_he {
461 struct refcounted_he *refcounted_he_next; /* next entry in chain */
463 U32 refcounted_he_hash;
464 U32 refcounted_he_keylen;
466 HEK *refcounted_he_hek; /* hint key */
469 IV refcounted_he_u_iv;
470 UV refcounted_he_u_uv;
471 STRLEN refcounted_he_u_len;
472 void *refcounted_he_u_ptr; /* Might be useful in future */
474 U32 refcounted_he_refcnt; /* reference count */
475 /* First byte is flags. Then NUL-terminated value. Then for ithreads,
476 non-NUL terminated key. */
477 char refcounted_he_data[1];
480 /* Flag bits are HVhek_UTF8, HVhek_WASUTF8, then */
481 #define HVrhek_undef 0x00 /* Value is undef. */
482 #define HVrhek_delete 0x10 /* Value is placeholder - signifies delete. */
483 #define HVrhek_IV 0x20 /* Value is IV. */
484 #define HVrhek_UV 0x30 /* Value is UV. */
485 #define HVrhek_PV 0x40 /* Value is a (byte) string. */
486 #define HVrhek_PV_UTF8 0x50 /* Value is a (utf8) string. */
487 /* Two spare. As these have to live in the optree, you can't store anything
488 interpreter specific, such as SVs. :-( */
489 #define HVrhek_typemask 0x70
492 /* A big expression to find the key offset */
493 #define REF_HE_KEY(chain) \
494 ((((chain->refcounted_he_data[0] & 0x60) == 0x40) \
495 ? chain->refcounted_he_val.refcounted_he_u_len + 1 : 0) \
496 + 1 + chain->refcounted_he_data)
500 # define HINTS_REFCNT_LOCK MUTEX_LOCK(&PL_hints_mutex)
501 # define HINTS_REFCNT_UNLOCK MUTEX_UNLOCK(&PL_hints_mutex)
503 # define HINTS_REFCNT_LOCK NOOP
504 # define HINTS_REFCNT_UNLOCK NOOP
509 # define HINTS_REFCNT_INIT MUTEX_INIT(&PL_hints_mutex)
510 # define HINTS_REFCNT_TERM MUTEX_DESTROY(&PL_hints_mutex)
512 # define HINTS_REFCNT_INIT NOOP
513 # define HINTS_REFCNT_TERM NOOP
517 * Passed in PERL_MAGIC_uvar calls
519 #define HV_DISABLE_UVAR_XKEY 0x01
520 /* We need to ensure that these don't clash with G_DISCARD, which is 2, as it
521 is documented as being passed to hv_delete(). */
522 #define HV_FETCH_ISSTORE 0x04
523 #define HV_FETCH_ISEXISTS 0x08
524 #define HV_FETCH_LVALUE 0x10
525 #define HV_FETCH_JUST_SV 0x20
526 #define HV_DELETE 0x40
531 Creates a new HV. The reference count is set to 1.
536 #define newHV() MUTABLE_HV(newSV_type(SVt_PVHV))
540 * c-indentation-style: bsd
542 * indent-tabs-mode: t
545 * ex: set ts=8 sts=4 sw=4 noet: