1MCE::Shared::Ordhash(3)User Contributed Perl DocumentatioMnCE::Shared::Ordhash(3)
2
6 MCE::Shared::Ordhash - An ordered hash class featuring tombstone
7 deletion
8
10 This document describes MCE::Shared::Ordhash version 1.873
11
13 An ordered-hash helper class for use as a standalone or managed by
14 MCE::Shared.
15 This module implements an ordered hash featuring tombstone deletion,
17 inspired by Hash::Ordered. An ordered hash is very much like a normal
18 hash but with key insertion order preserved.
19 It provides "splice", sorting, plus extra capabilities for use with
21 MCE::Shared::Minidb. Tombstone deletion is further optimized to not
22 impact "store", "push", "unshift", and "merge". Tombstones are purged
23 in-place for lesser memory consumption. In addition, "pop" and "shift"
24 run optimally when an index is present. The optimization also applies
25 to forward and reverse deletes. The end result is achieving a new level
26 of performance, for a pure-Perl ordered hash implementation.
27
29 # non-shared or local construction for use by a single process
30 use MCE::Shared::Ordhash;
32 my $oh = MCE::Shared::Ordhash->new( @pairs );
34 # construction for sharing with other threads and processes
36 use MCE::Shared;
38 my $oh = MCE::Shared->ordhash( @pairs );
40 # hash-like dereferencing
42 my $val = $oh->{$key};
44 $oh->{$key} = $val;
45 %{$oh} = ();
47 # OO interface
49 if ( !defined ( $val = $oh->get("some_key") ) ) {
51 $val = $oh->set( some_key => "some_value" );
52 }
53 $val = $oh->set( $key, $val );
55 $ret = $oh->setnx( $key, $val ); # set only if the key exists
56 $val = $oh->get( $key );
57 $val = $oh->delete( $key ); # del is an alias for delete
58 $bool = $oh->exists( $key );
59 void = $oh->clear();
60 $len = $oh->len(); # scalar keys %{ $oh }
61 $len = $oh->len( $key ); # length $oh->{ $key }
62 @pair = $oh->pop();
63 $len = $oh->push( @pairs );
64 @pair = $oh->shift();
65 $len = $oh->unshift( @pairs );
66 %pairs = $oh->splice( $offset, $length, @pairs );
67 $oh2 = $oh->clone( @keys ); # @keys is optional
69 $oh3 = $oh->flush( @keys );
70 $iter = $oh->iterator( @keys ); # ($key, $val) = $iter->()
71 @keys = $oh->keys( @keys );
72 %pairs = $oh->pairs( @keys );
73 @vals = $oh->values( @keys ); # vals is an alias for values
74 $len = $oh->assign( $key/$val pairs ); # equivalent to ->clear, ->mset
76 $cnt = $oh->mdel( @keys );
77 @vals = $oh->mget( @keys );
78 $bool = $oh->mexists( @keys ); # true if all keys exists
79 $len = $oh->mset( $key/$val pairs ); # merge is an alias for mset
80 @vals = $oh->sort(); # by val $a <=> $b default
82 @vals = $oh->sort( "desc" ); # by val $b <=> $a
83 @vals = $oh->sort( "alpha" ); # by val $a cmp $b
84 @vals = $oh->sort( "alpha desc" ); # by val $b cmp $a
85 @vals = $oh->sort( "key" ); # by key $a <=> $b
87 @vals = $oh->sort( "key desc" ); # by key $b <=> $a
88 @vals = $oh->sort( "key alpha" ); # by key $a cmp $b
89 @vals = $oh->sort( "key alpha desc" ); # by key $b cmp $a
90 # included, sugar methods without having to call set/get explicitly
92 $len = $oh->append( $key, $string ); # $val .= $string
94 $val = $oh->decr( $key ); # --$val
95 $val = $oh->decrby( $key, $number ); # $val -= $number
96 $val = $oh->getdecr( $key ); # $val--
97 $val = $oh->getincr( $key ); # $val++
98 $val = $oh->incr( $key ); # ++$val
99 $val = $oh->incrby( $key, $number ); # $val += $number
100 $old = $oh->getset( $key, $new ); # $o = $v, $v = $n, $o
101 # pipeline, provides atomicity for shared objects, MCE::Shared v1.09+
103 @vals = $oh->pipeline( # ( "a_a", "b_b", "c_c" )
105 [ "set", foo => "a_a" ],
106 [ "set", bar => "b_b" ],
107 [ "set", baz => "c_c" ],
108 [ "mget", qw/ foo bar baz / ]
109 );
110 For normal hash behavior, the TIE interface is supported.
112 # non-shared or local construction for use by a single process
114 use MCE::Shared::Ordhash;
116 tie my %oh, "MCE::Shared::Ordhash", @pairs;
118 tie my %oh, "MCE::Shared::Ordhash";
119 # construction for sharing with other threads and processes
121 # the ordered option is needed to know to use MCE::Shared::Ordhash
122 use MCE::Shared;
124 tie my %oh, "MCE::Shared", { ordered => 1 }, @pairs;
126 tie my %oh, "MCE::Shared", ordered => 1;
127 # usage
129 my $val;
131 if ( !defined ( $val = $oh{some_key} ) ) {
133 $val = $oh{some_key} = "some_value";
134 }
135 $oh{some_key} = 0;
137 tied(%oh)->incrby("some_key", 20);
139 tied(%oh)->incrby(some_key => 20);
140
142 Several methods take a query string for an argument. The format of the
143 string is described below. In the context of sharing, the query
144 mechanism is beneficial for the shared-manager process. It is able to
145 perform the query where the data resides versus the client-process grep
146 locally involving lots of IPC.
147 o Basic demonstration
149 @keys = $oh->keys( "query string given here" );
151 @keys = $oh->keys( "val =~ /pattern/" );
152 o Supported operators: =~ !~ eq ne lt le gt ge == != < <= > >=
154 o Multiple expressions delimited by :AND or :OR, mixed case allowed
155 "key eq 'some key' :or (val > 5 :and val < 9)"
157 "key eq some key :or (val > 5 :and val < 9)"
158 "key =~ /pattern/i :And val =~ /pattern/i"
159 "val eq foo baz :OR key !~ /pattern/i"
160 * key matches on keys in the hash
162 * likewise, val matches on values
163 o Quoting is optional inside the string
165 "key =~ /pattern/i :AND val eq 'foo bar'" # val eq "foo bar"
167 "key =~ /pattern/i :AND val eq foo bar" # val eq "foo bar"
168 Examples.
170 # search capability key/val: =~ !~ eq ne lt le gt ge == != < <= > >=
172 # key/val means to match against actual key/val respectively
173 @keys = $oh->keys( "key eq 'some key' :or (val > 5 :and val < 9)" );
175 @keys = $oh->keys( "key eq some key :or (val > 5 :and val < 9)" );
176 @keys = $oh->keys( "key =~ /$pattern/i" );
178 @keys = $oh->keys( "key !~ /$pattern/i" );
179 @keys = $oh->keys( "val =~ /$pattern/i" );
180 @keys = $oh->keys( "val !~ /$pattern/i" );
181 %pairs = $oh->pairs( "key == $number" );
183 %pairs = $oh->pairs( "key != $number :and val > 100" );
184 %pairs = $oh->pairs( "key < $number :or key > $number" );
185 %pairs = $oh->pairs( "val <= $number" );
186 %pairs = $oh->pairs( "val > $number" );
187 %pairs = $oh->pairs( "val >= $number" );
188 @vals = $oh->vals( "key eq $string" );
190 @vals = $oh->vals( "key ne $string with space" );
191 @vals = $oh->vals( "key lt $string :or val =~ /$pat1|$pat2/" );
192 @vals = $oh->vals( "val le $string :and val eq 'foo bar'" );
193 @vals = $oh->vals( "val le $string :and val eq foo bar" );
194 @vals = $oh->vals( "val gt $string" );
195 @vals = $oh->vals( "val ge $string" );
196
198 This module involves TIE when accessing the object via hash-like
199 behavior. Both non-shared and shared instances are impacted if doing
200 so. Although likely fast enough for many use cases, the OO interface is
201 recommended for best performance.
202 MCE::Shared::Ordhash->new ( key, value [, key, value, ... ] )
204 MCE::Shared->ordhash ( key, value [, key, value, ... ] )
205 Constructs a new object, with an optional list of key-value pairs.
206 # non-shared or local construction for use by a single process
208 use MCE::Shared::Ordhash;
210 $oh = MCE::Shared::Ordhash->new( @pairs );
212 $oh = MCE::Shared::Ordhash->new( );
213 # construction for sharing with other threads and processes
215 use MCE::Shared;
217 $oh = MCE::Shared->ordhash( @pairs );
219 $oh = MCE::Shared->ordhash( );
220 assign ( key, value [, key, value, ... ] )
222 Clears the hash, then sets multiple key-value pairs and returns the
223 number of keys stored in the hash. This is equivalent to "clear",
224 "mset".
225 $len = $oh->assign( "key1" => "val1", "key2" => "val2" ); # 2
227 $len = %{$oh} = ( "key1" => "val1", "key2" => "val2" ); # 4
228 API available since 1.007.
230 clear
232 Removes all key-value pairs from the hash.
233 $oh->clear;
235 %{$oh} = ();
236 clone ( key [, key, ... ] )
238 Creates a shallow copy, a "MCE::Shared::Ordhash" object. It returns an
239 exact copy if no arguments are given. Otherwise, the object includes
240 only the given keys in the same order. Keys that do not exist in the
241 hash will have the "undef" value.
242 $oh2 = $oh->clone( "key1", "key2" );
244 $oh2 = $oh->clone;
245 delete ( key )
247 Deletes and returns the value by given key or "undef" if the key does
248 not exists in the hash.
249 $val = $oh->delete( "some_key" );
251 $val = delete $oh->{ "some_key" };
252 del
254 "del" is an alias for "delete".
255 exists ( key )
257 Determines if a key exists in the hash.
258 if ( $oh->exists( "some_key" ) ) { ... }
260 if ( exists $oh->{ "some_key" } ) { ... }
261 flush ( key [, key, ... ] )
263 Same as "clone". Though, clears all existing items before returning.
264 get ( key )
266 Gets the value of a hash key or "undef" if the key does not exists.
267 $val = $oh->get( "some_key" );
269 $val = $oh->{ "some_key" };
270 iterator ( key [, key, ... ] )
272 Returns a code reference for iterating a list of key-value pairs stored
273 in the hash when no arguments are given. Otherwise, returns a code
274 reference for iterating the given keys in the same order. Keys that do
275 not exist will have the "undef" value.
276 The list of keys to return is set when the closure is constructed.
278 Later keys added to the hash are not included. Subsequently, the
279 "undef" value is returned for deleted keys.
280 $iter = $oh->iterator;
282 $iter = $oh->iterator( "key1", "key2" );
283 while ( my ( $key, $val ) = $iter->() ) {
285 ...
286 }
287 iterator ( "query string" )
289 Returns a code reference for iterating a list of key-value pairs that
290 match the given criteria. It returns an empty list if the search found
291 nothing. The syntax for the "query string" is described above.
292 $iter = $oh->iterator( "val eq some_value" );
294 $iter = $oh->iterator( "key eq some_key :AND val =~ /sun|moon|air|wind/" );
295 $iter = $oh->iterator( "val eq sun :OR val eq moon :OR val eq foo" );
296 $iter = $oh->iterator( "key =~ /$pattern/" );
297 while ( my ( $key, $val ) = $iter->() ) {
299 ...
300 }
301 keys ( key [, key, ...] )
303 Returns hash keys in the same insertion order when no arguments are
304 given. Otherwise, returns the given keys in the same order. Keys that
305 do not exist will have the "undef" value. In scalar context, returns
306 the size of the hash.
307 @keys = $oh->keys( "key1", "key2" );
309 @keys = $oh->keys; # faster
311 @keys = keys %{$oh}; # involves TIE overhead
312 $len = $oh->keys; # ditto
314 $len = keys %{$oh};
315 keys ( "query string" )
317 Returns only keys that match the given criteria. It returns an empty
318 list if the search found nothing. The syntax for the "query string" is
319 described above. In scalar context, returns the size of the resulting
320 list.
321 @keys = $oh->keys( "val eq some_value" );
323 @keys = $oh->keys( "key eq some_key :AND val =~ /sun|moon|air|wind/" );
324 @keys = $oh->keys( "val eq sun :OR val eq moon :OR val eq foo" );
325 $len = $oh->keys( "key =~ /$pattern/" );
326 len ( key )
328 Returns the size of the hash when no arguments are given. For the given
329 key, returns the length of the value stored at key or the "undef" value
330 if the key does not exists.
331 $size = $oh->len;
333 $len = $oh->len( "key1" );
334 $len = length $oh->{ "key1" };
335 mdel ( key [, key, ... ] )
337 Deletes one or more keys in the hash and returns the number of keys
338 deleted. A given key which does not exist in the hash is not counted.
339 $cnt = $oh->mdel( "key1", "key2" );
341 mexists ( key [, key, ... ] )
343 Returns a true value if all given keys exists in the hash. A false
344 value is returned otherwise.
345 if ( $oh->mexists( "key1", "key2" ) ) { ... }
347 mget ( key [, key, ... ] )
349 Gets the values of all given keys. It returns "undef" for keys which do
350 not exists in the hash.
351 ( $val1, $val2 ) = $oh->mget( "key1", "key2" );
353 mset ( key, value [, key, value, ... ] )
355 Sets multiple key-value pairs in a hash and returns the number of keys
356 stored in the hash.
357 $len = $oh->mset( "key1" => "val1", "key2" => "val2" );
359 merge
361 "merge" is an alias for "mset".
362 pairs ( key [, key, ... ] )
364 Returns key-value pairs in the same insertion order when no arguments
365 are given. Otherwise, returns key-value pairs for the given keys in
366 the same order. Keys that do not exist will have the "undef" value. In
367 scalar context, returns the size of the hash.
368 @pairs = $oh->pairs( "key1", "key2" );
370 @pairs = $oh->pairs;
372 $len = $oh->pairs;
373 pairs ( "query string" )
375 Returns only key-value pairs that match the given criteria. It returns
376 an empty list if the search found nothing. The syntax for the "query
377 string" is described above. In scalar context, returns the size of the
378 resulting list.
379 @pairs = $oh->pairs( "val eq some_value" );
381 @pairs = $oh->pairs( "key eq some_key :AND val =~ /sun|moon|air|wind/" );
382 @pairs = $oh->pairs( "val eq sun :OR val eq moon :OR val eq foo" );
383 $len = $oh->pairs( "key =~ /$pattern/" );
384 pipeline ( [ func1, @args ], [ func2, @args ], ... )
386 Combines multiple commands for the object to be processed serially. For
387 shared objects, the call is made atomically due to single IPC to the
388 shared-manager process. The "pipeline" method is fully
389 "wantarray"-aware and receives a list of commands and their arguments.
390 In scalar or list context, it returns data from the last command in the
391 pipeline.
392 @vals = $oh->pipeline( # ( "a_a", "b_b", "c_c" )
394 [ "set", foo => "a_a" ],
395 [ "set", bar => "b_b" ],
396 [ "set", baz => "c_c" ],
397 [ "mget", qw/ foo bar baz / ]
398 );
399 $len = $oh->pipeline( # 3, same as $oh->len
401 [ "set", foo => "i_i" ],
402 [ "set", bar => "j_j" ],
403 [ "set", baz => "k_k" ],
404 [ "len" ]
405 );
406 $oh->pipeline(
408 [ "set", foo => "m_m" ],
409 [ "set", bar => "n_n" ],
410 [ "set", baz => "o_o" ]
411 );
412 Current API available since 1.809.
414 pipeline_ex ( [ func1, @args ], [ func2, @args ], ... )
416 Same as "pipeline", but returns data for every command in the pipeline.
417 @vals = $oh->pipeline_ex( # ( "a_a", "b_b", "c_c" )
419 [ "set", foo => "a_a" ],
420 [ "set", bar => "b_b" ],
421 [ "set", baz => "c_c" ]
422 );
423 Current API available since 1.809.
425 pop
427 Removes and returns the last key-value pair or value in scalar context
428 of the ordered hash. If there are no keys in the hash, returns the
429 undefined value.
430 ( $key, $val ) = $oh->pop;
432 $val = $oh->pop;
434 purge
436 A utility method for purging any *tombstones* in the keys array. It
437 also resets a couple counters internally. Call this method before
438 serializing to a file, which is the case in "MCE::Shared::Minidb".
439 $oh->purge;
441 push ( key, value [, key, value, ... ] )
443 Appends one or multiple key-value pairs to the tail of the ordered hash
444 and returns the new length. Any keys already existing in the hash are
445 re-inserted with the new values.
446 $len = $oh->push( "key1", "val1", "key2", "val2" );
448 set ( key, value )
450 Sets the value of the given hash key and returns its new value.
451 $val = $oh->set( "key", "value" );
453 $val = $oh->{ "key" } = "value";
454 setnx ( key, value )
456 Sets the value of a hash key, only if the key does not exist. Returns a
457 1 for new key or 0 if the key already exists and no operation was
458 performed.
459 $ret = $oh->setnx( "key", "value" );
461 Current API available since 1.872.
463 shift
465 Removes and returns the first key-value pair or value in scalar context
466 of the ordered hash. If there are no keys in the hash, returns the
467 undefined value.
468 ( $key, $val ) = $oh->shift;
470 $val = $oh->shift;
472 sort ( "BY key [ ASC | DESC ] [ ALPHA ]" )
474 sort ( "BY val [ ASC | DESC ] [ ALPHA ]" )
475 Returns sorted keys in list context, leaving the elements intact. In
476 void context, sorts the hash in-place. By default, sorting is numeric
477 and applied to values when no arguments are given.
478 @keys = $oh->sort( "BY val" );
480 $oh->sort();
482 If the keys or values contain string values and you want to sort them
484 lexicographically, specify the "ALPHA" modifier.
485 @keys = $oh->sort( "BY key ALPHA" );
487 $oh->sort( "BY val ALPHA" );
489 The default is "ASC" for sorting the hash from small to large. In order
491 to sort the hash from large to small, specify the "DESC" modifier.
492 @keys = $oh->sort( "BY val DESC ALPHA" );
494 $oh->sort( "BY key DESC ALPHA" );
496 splice ( offset [, length [, key, value, ... ] ] )
498 Removes the key-value pairs designated by "offset" and "length" from
499 the ordered hash, and replaces them with "key-value pairs", if any. The
500 behavior is similar to the Perl "splice" function.
501 @pairs = $oh->splice( 20, 2, @pairs );
503 @pairs = $oh->splice( 20, 2 );
504 @pairs = $oh->splice( 20 );
505 unshift ( key, value [, key, value, ... ] )
507 Prepends one or multiple key-value pairs to the head of the ordered
508 hash and returns the new length. Any keys already existing in the hash
509 are re-inserted with the new values.
510 $len = $oh->unshift( "key1", "val1", "key2", "val2" );
512 values ( key [, key, ... ] )
514 Returns hash values in the same insertion order when no arguments are
515 given. Otherwise, returns values for the given keys in the same order.
516 Keys that do not exist will have the "undef" value. In scalar context,
517 returns the size of the hash.
518 @vals = $oh->values( "key1", "key2" );
520 @vals = $oh->values; # faster
522 @vals = values %{$oh}; # involves TIE overhead
523 $len = $oh->values; # ditto
525 $len = values %{$oh};
526 values ( "query string" )
528 Returns only values that match the given criteria. It returns an empty
529 list if the search found nothing. The syntax for the "query string" is
530 described above. In scalar context, returns the size of the resulting
531 list.
532 @vals = $oh->values( "val eq some_value" );
534 @vals = $oh->values( "key eq some_key :AND val =~ /sun|moon|air|wind/" );
535 @vals = $oh->values( "val eq sun :OR val eq moon :OR val eq foo" );
536 $len = $oh->values( "key =~ /$pattern/" );
537 vals
539 "vals" is an alias for "values".
540
542 This module is equipped with sugar methods to not have to call "set"
543 and "get" explicitly. In shared context, the benefit is atomicity and
544 reduction in inter-process communication.
545 The API resembles a subset of the Redis primitives
547 <http://redis.io/commands#strings> with key representing the hash key.
548 append ( key, string )
550 Appends a value to a key and returns its new length.
551 $len = $oh->append( $key, "foo" );
553 decr ( key )
555 Decrements the value of a key by one and returns its new value.
556 $num = $oh->decr( $key );
558 decrby ( key, number )
560 Decrements the value of a key by the given number and returns its new
561 value.
562 $num = $oh->decrby( $key, 2 );
564 getdecr ( key )
566 Decrements the value of a key by one and returns its old value.
567 $old = $oh->getdecr( $key );
569 getincr ( key )
571 Increments the value of a key by one and returns its old value.
572 $old = $oh->getincr( $key );
574 getset ( key, value )
576 Sets the value of a key and returns its old value.
577 $old = $oh->getset( $key, "baz" );
579 incr ( key )
581 Increments the value of a key by one and returns its new value.
582 $num = $oh->incr( $key );
584 incrby ( key, number )
586 Increments the value of a key by the given number and returns its new
587 value.
588 $num = $oh->incrby( $key, 2 );
590
592 Many thanks to David Golden for Hash::Ordered. This implementation is
593 inspired by Hash::Ordered v0.009.
594
596 I wanted an ordered hash implementation for use with MCE::Shared
597 without any side effects. For example, linear scans, slow deletes, or
598 excessive memory consumption. The closest module on CPAN to pass in
599 this regard is Hash::Ordered by David Golden.
600 MCE::Shared has only one shared-manager process which is by design.
602 Therefore, re-factored tombstone deletion with extras for lesser impact
603 to the rest of the library. This module differs in personality from
604 Hash::Ordered mainly for compatibility with the other classes included
605 with MCE::Shared.
606 The following simulates a usage pattern inside MCE::Hobo involving
608 random key deletion. For example, an application joining a list of
609 Hobos provided by "MCE::Hobo->list_joinable".
610 use MCE::Shared::Ordhash;
612 use List::Util 'shuffle';
613 use Time::HiRes 'time';
614 srand 0;
616 my $oh = MCE::Shared::Ordhash->new();
618 my $num_keys = 200000;
619 my $start = time();
620 $oh->set($_,$_) for 1 .. $num_keys;
622 for ( shuffle $oh->keys ) {
624 $oh->delete($_);
625 }
626 printf "duration: %7.03f secs\n", time() - $start;
628 Both the runtime and memory consumption are captured for the
630 demonstration. Results are included for MCE::Shared::Hash (unordered
631 hash) for comparison.
632 for ( shuffle $oh->keys ) { $oh->delete($_) }
634 0.378 secs. 35 MB MCE::Shared::Hash (unordered)
636 0.437 secs. 49 MB Tie::Hash::Indexed (XS)
637 0.743 secs. 54 MB MCE::Shared::Ordhash
638 1.028 secs. 60 MB Hash::Ordered
639 1.752 secs. 112 MB Tie::LLHash
640 > 42 mins. 66 MB Tie::IxHash
641 Using the same demonstration above, another usage pattern inside
643 MCE::Hobo involves orderly hash-key deletion. For example, waiting for
644 and joining all Hobos provided by "MCE::Hobo->list".
645 for ( $oh->keys ) { $oh->delete($_) }
647 0.353 secs. 35 MB MCE::Shared::Hash (unordered)
649 0.349 secs. 49 MB Tie::Hash::Indexed (XS)
650 0.452 secs. 41 MB MCE::Shared::Ordhash
651 0.735 secs. 54 MB Hash::Ordered
652 1.338 secs. 112 MB Tie::LLHash
653 > 42 mins. 66 MB Tie::IxHash
654 No matter if orderly or randomly, even backwards, hash-key deletion in
656 "MCE::Shared::Ordhash" performs reasonably well. The following provides
657 the construction used for the modules mentioned.
658 my $oh = Hash::Ordered->new();
660 $oh->set($_,$_); $oh->keys; $oh->delete($_);
661 my $oh = Tie::Hash::Indexed->new();
663 $oh->set($_,$_); $oh->keys; $oh->delete($_);
664 my $oh = Tie::IxHash->new();
666 $oh->STORE($_,$_); $oh->Keys; $oh->DELETE($_);
667 my $oh = tie my %hash, 'Tie::LLHash';
669 $oh->last($_,$_); keys %hash; $oh->DELETE($_);
670 Hash::Ordered is supported for use with MCE::Shared. This includes on-
672 demand hash-like dereferencing, similarly to "hash" and "ordhash".
673 use feature 'say';
675 use MCE::Hobo;
677 use MCE::Shared;
678 use Hash::Ordered; # 0.010 or later
679 my $ha = MCE::Shared->hash(); # shared MCE::Shared::Hash
681 my $oh = MCE::Shared->ordhash(); # shared MCE::Shared::Ordhash
682 my $ho = MCE::Shared->share( Hash::Ordered->new() );
684 sub parallel_task {
686 my ($id) = @_;
687 # OO interface
689 if ($id == 1) {
690 $ha->set("$id", "foo");
691 $oh->set("$id", "foo");
692 $ho->set("$id", "foo");
693 }
694 # hash-like dereferencing
695 elsif ($id == 2) {
696 $ha->{"$id"} = "baz";
697 $oh->{"$id"} = "baz";
698 $ho->{"$id"} = "baz";
699 }
700 return;
702 }
703 MCE::Hobo->create("parallel_task", $_) for 1..2;
705 MCE::Hobo->waitall;
706 say $ha->{"1"}; # foo
708 say $oh->{"1"};
709 say $ho->{"1"};
710 say $ha->get("2"); # baz
712 say $oh->get("2");
713 say $ho->get("2");
714
716 • Hash::Ordered
717 • Tie::Hash::Indexed
719 • Tie::IxHash
721 • Tie::LLHash
723
725 MCE, MCE::Hobo, MCE::Shared
726
728 Mario E. Roy, <marioeroy AT gmail DOT com>
729perl v5.32.1 2021-01-27 MCE::Shared::Ordhash(3)