Date: Saturday December 28, 2019 @ 02:29
Author: argrath
Update of /cvsroot/perldocjp/docs/modules/feature-1.42
In directory sf-cvs:/tmp/cvs-serv125770/modules/feature-1.42
Added Files:
feature.pod
Log Message:
feature-1.42
===================================================================
File: feature.pod Status: Up-to-date
Working revision: 1.1 Fri Dec 27 17:29:28 2019
Repository revision: 1.1 /cvsroot/perldocjp/docs/modules/feature-1.42/feature.pod,v
Existing Tags:
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-------------- next part --------------
Index: docs/modules/feature-1.42/feature.pod
diff -u /dev/null docs/modules/feature-1.42/feature.pod:1.1
--- /dev/null Sat Dec 28 02:29:28 2019
+++ docs/modules/feature-1.42/feature.pod Sat Dec 28 02:29:28 2019
@@ -0,0 +1,897 @@
+
+=encoding euc-jp
+
+=head1 NAME
+
+=begin original
+
+feature - Perl pragma to enable new features
+
+=end original
+
+feature - ¿·¤·¤¤µ¡Ç½¤ò͸ú¤Ë¤¹¤ë¥×¥é¥°¥Þ
+
+=head1 SYNOPSIS
+
+ use feature qw(say switch);
+ given ($foo) {
+ when (1) { say "\$foo == 1" }
+ when ([2,3]) { say "\$foo == 2 || \$foo == 3" }
+ when (/^a[bc]d$/) { say "\$foo eq 'abd' || \$foo eq 'acd'" }
+ when ($_ > 100) { say "\$foo > 100" }
+ default { say "None of the above" }
+ }
+
+ use feature ':5.10'; # loads all features available in perl 5.10
+
+ use v5.10; # implicitly loads :5.10 feature bundle
+
+=head1 DESCRIPTION
+
+=begin original
+
+It is usually impossible to add new syntax to Perl without breaking
+some existing programs. This pragma provides a way to minimize that
+risk. New syntactic constructs, or new semantic meanings to older
+constructs, can be enabled by C<use feature 'foo'>, and will be parsed
+only when the appropriate feature pragma is in scope. (Nevertheless, the
+C<CORE::> prefix provides access to all Perl keywords, regardless of this
+pragma.)
+
+=end original
+
+´û¤Ë¸ºß¤·¤Æ¤¤¤ë¥×¥í¥°¥é¥à¤ò²õ¤¹¤³¤È¤Ê¤¯¡¢Perl ¤Ë¿·¤·¤¤Ê¸Ë¡¤òÄɲ乤뤳¤È¤Ï¡¢
+ÉáÄ̤ÏÉÔ²Äǽ¤Ç¤¹¡£
+¤³¤Î¥×¥é¥°¥Þ¤Ï¡¢¥ê¥¹¥¯¤òºÇ¾®²½¤¹¤ëÊýË¡¤òÄ󶡤·¤Þ¤¹¡£
+¿·¤·¤¤Ê¸Ë¡¹½Â¤¤ä¡¢¸Å¤¤¹½Â¤¤Î¿·¤·¤¤°ÕÌ£¤Ï¡¢C<use feature 'foo'> ¤Ç͸ú²½¤µ¤ì¡¢
+ŬÀÚ¤Ê feature ¥×¥é¥°¥Þ¤¬¥¹¥³¡¼¥×Æâ¤Ë¤¢¤ë¾ì¹ç¤Ë¤Î¤ß¥Ñ¡¼¥¹¤µ¤ì¤Þ¤¹¡£
+(¤½¤ì¤Ç¤â¡¢¤³¤Î¥×¥é¥°¥Þ¤Ë´Ø¤ï¤é¤º¡¢C<CORE::> ÀÜƬ¼¤ÏÁ´¤Æ¤Î
+Perl ¥¡¼¥ï¡¼¥É¤Ø¤Î¥¢¥¯¥»¥¹¤òÄ󶡤·¤Þ¤¹¡£)
+
+=head2 Lexical effect
+
+(¥ì¥¥·¥«¥ë¤Ê¸ú²Ì)
+
+=begin original
+
+Like other pragmas (C<use strict>, for example), features have a lexical
+effect. C<use feature qw(foo)> will only make the feature "foo" available
+from that point to the end of the enclosing block.
+
+=end original
+
+(Î㤨¤Ð C<use strict> ¤Î¤è¤¦¤Ê) ¤½¤Î¾¤Î¥×¥é¥°¥Þ¤ÈƱÍÍ¡¢feature ¤Ï
+¥ì¥¥·¥«¥ë¤Ê¸ú²Ì¤ò»ý¤Á¤Þ¤¹¡£
+C<use feature qw(foo)> ¤Ï¡¢¤³¤ÎÃÏÅÀ¤«¤é¥Ö¥í¥Ã¥¯¤Î½ª¤ï¤ê¤Þ¤Ç¤Î´Ö¤À¤±¡¢
+"foo" µ¡Ç½¤òÍøÍѲÄǽ¤Ë¤·¤Þ¤¹¡£
+
+ {
+ use feature 'say';
+ say "say is available here";
+ }
+ print "But not here.\n";
+
+=head2 C<no feature>
+
+=begin original
+
+Features can also be turned off by using C<no feature "foo">. This too
+has lexical effect.
+
+=end original
+
+µ¡Ç½¤Ï C<no feature "foo"> ¤ò»È¤¦¤³¤È¤Ç̵¸ú¤Ë¤¹¤ë¤³¤È¤â½ÐÍè¤Þ¤¹¡£
+¤³¤ì¤â¤Þ¤¿¥ì¥¥·¥«¥ë¤Ê¸ú²Ì¤ò»ý¤Á¤Þ¤¹¡£
+
+ use feature 'say';
+ say "say is available here";
+ {
+ no feature 'say';
+ print "But not here.\n";
+ }
+ say "Yet it is here.";
+
+=begin original
+
+C<no feature> with no features specified will reset to the default group. To
+disable I<all> features (an unusual request!) use C<no feature ':all'>.
+
+=end original
+
+C<no feature> ¤È¡¢µ¡Ç½¤ò»ØÄꤻ¤º¤Ë»È¤¦¤È¡¢¥Ç¥Õ¥©¥ë¥È¥°¥ë¡¼¥×¤Ë¥ê¥»¥Ã¥È¤·¤Þ¤¹¡£
+I<Á´¤Æ¤Î> µ¡Ç½¤ò̵¸ú¤Ë¤¹¤ë(ÉáÄ̤Ǥʤ¤Í×µá!)¤Ë¤Ï¡¢C<no feature ':all'> ¤ò
+»È¤Ã¤Æ¤¯¤À¤µ¤¤¡£
+
+=head1 AVAILABLE FEATURES
+
+(ÍøÍѲÄǽ¤Êµ¡Ç½)
+
+=head2 The 'say' feature
+
+('say' µ¡Ç½)
+
+=begin original
+
+C<use feature 'say'> tells the compiler to enable the Perl 6 style
+C<say> function.
+
+=end original
+
+C<use feature 'say'> ¤Ï¡¢¥³¥ó¥Ñ¥¤¥é¤Ë Perl 6 ·Á¼°¤Î C<say> ´Ø¿ô¤ò
+͸ú¤Ë¤¹¤ë¤è¤¦¤ËÅÁ¤¨¤Þ¤¹¡£
+
+=begin original
+
+See L<perlfunc/say> for details.
+
+=end original
+
+¾Ü¤·¤¯¤Ï L<perlfunc/say> ¤ò»²¾È¤·¤Æ¤¯¤À¤µ¤¤¡£
+
+=begin original
+
+This feature is available starting with Perl 5.10.
+
+=end original
+
+¤³¤Îµ¡Ç½¤Ï Perl 5.10 ¤«¤éÍøÍѲÄǽ¤Ç¤¹¡£
+
+=head2 The 'state' feature
+
+('state' µ¡Ç½)
+
+=begin original
+
+C<use feature 'state'> tells the compiler to enable C<state>
+variables.
+
+=end original
+
+C<use feature 'state'> ¤Ï¡¢¥³¥ó¥Ñ¥¤¥é¤Ë C<state> ÊÑ¿ô¤ò͸ú¤Ë¤¹¤ë¤è¤¦¤Ë
+ÅÁ¤¨¤Þ¤¹¡£
+
+=begin original
+
+See L<perlsub/"Persistent Private Variables"> for details.
+
+=end original
+
+¾Ü¤·¤¯¤Ï L<perlsub/"Persistent Private Variables"> ¤ò»²¾È¤·¤Æ¤¯¤À¤µ¤¤¡£
+
+=begin original
+
+This feature is available starting with Perl 5.10.
+
+=end original
+
+¤³¤Îµ¡Ç½¤Ï Perl 5.10 ¤«¤éÍøÍѲÄǽ¤Ç¤¹¡£
+
+=head2 The 'switch' feature
+
+('switch' µ¡Ç½)
+
+=begin original
+
+B<WARNING>: Because the L<smartmatch operator|perlop/"Smartmatch Operator"> is
+experimental, Perl will warn when you use this feature, unless you have
+explicitly disabled the warning:
+
+=end original
+
+B<WARNING>: L<¥¹¥Þ¡¼¥È¥Þ¥Ã¥Á¥ó¥°±é»»»Ò|perlop/"Smartmatch Operator"> ¤Ï
+¼Â¸³Åª¤Ê¤Î¤Ç¡¢¤³¤Îµ¡Ç½¤ò»È¤¦¤È¡¢ÌÀ¼¨Åª¤Ë̵¸ú¤Ë¤·¤Ê¤¤¸Â¤ê·Ù¹ð¤¬È¯À¸¤·¤Þ¤¹:
+
+ no warnings "experimental::smartmatch";
+
+=begin original
+
+C<use feature 'switch'> tells the compiler to enable the Perl 6
+given/when construct.
+
+=end original
+
+C<use feature 'switch'> ¤Ï¡¢¥³¥ó¥Ñ¥¤¥é¤Ë Perl 6 given/when ¹½Ê¸¤ò
+͸ú¤Ë¤¹¤ë¤è¤¦¤ËÅÁ¤¨¤Þ¤¹¡£
+
+=begin original
+
+See L<perlsyn/"Switch Statements"> for details.
+
+=end original
+
+¾Ü¤·¤¯¤Ï L<perlsyn/"Switch Statements"> ¤ò»²¾È¤·¤Æ¤¯¤À¤µ¤¤¡£
+
+=begin original
+
+This feature is available starting with Perl 5.10.
+
+=end original
+
+¤³¤Îµ¡Ç½¤Ï Perl 5.10 ¤«¤éÍøÍѲÄǽ¤Ç¤¹¡£
+
+=head2 The 'unicode_strings' feature
+
+('unicode_strings' µ¡Ç½)
+
+=begin original
+
+C<use feature 'unicode_strings'> tells the compiler to use Unicode rules
+in all string operations executed within its scope (unless they are also
+within the scope of either C<use locale> or C<use bytes>). The same applies
+to all regular expressions compiled within the scope, even if executed outside
+it. It does not change the internal representation of strings, but only how
+they are interpreted.
+
+=end original
+
+C<use feature 'unicode_strings'> ¤Ï¡¢(C<use locale> ¤« C<use bytes> ¤Î
+¥¹¥³¡¼¥×¤Ê¤¤¤Ç¤Ê¤¤¸Â¤ê) ¤½¤Î¥¹¥³¡¼¥×Æâ¤Ç¼Â¹Ô¤µ¤ì¤ëÁ´¤Æ¤Îʸ»úÎóÁàºî¤Ë
+Unicode ¤Îµ¬Â§¤ò»È¤¦¤è¤¦¤Ë¥³¥ó¥Ñ¥¤¥é¤ËÅÁ¤¨¤Þ¤¹¡£
+¤³¤ì¤Ïʸ»úÎó¤ÎÆâÉôɽ¸½¤ÏÊѹ¹¤·¤Þ¤»¤ó; ¤½¤ì¤ò¤É¤¦²ò¼á¤¹¤ë¤«¤À¤±¤Ç¤¹¡£
+
+=begin original
+
+C<no feature 'unicode_strings'> tells the compiler to use the traditional
+Perl rules wherein the native character set rules is used unless it is
+clear to Perl that Unicode is desired. This can lead to some surprises
+when the behavior suddenly changes. (See
+L<perlunicode/The "Unicode Bug"> for details.) For this reason, if you are
+potentially using Unicode in your program, the
+C<use feature 'unicode_strings'> subpragma is B<strongly> recommended.
+
+=end original
+
+C<no feature 'unicode_strings'> ¤Ï¡¢Unicode ¤¬µá¤á¤é¤ì¤Æ¤¤¤ë¤Î¤¬
+Perl ¤Ë¤È¤Ã¤ÆÌÀ¤é¤«¤Ç¤Ê¤¤¸Â¤ê¡¢¥Í¥¤¥Æ¥£¥Ö¤Êʸ»ú½¸¹çµ¬Â§¤¬»È¤ï¤ì¤ë¤È¤³¤í¤Ç
+ÅÁÅýŪ¤Ê Perl ¤Îµ¬Â§¤ò»È¤¦¤è¤¦¤Ë¥³¥ó¥Ñ¥¤¥é¤ËÅÁ¤¨¤Þ¤¹¡£
+¤³¤ì¤Ï¡¢¿¶¤ëÉñ¤¤¤¬ÆÍÁ³Êѹ¹¤µ¤ì¤¿¤È¤¤Ë¶Ã¤¤ò°ú¤µ¯¤³¤¹¤«¤â¤·¤ì¤Þ¤»¤ó¡£
+(¾Ü¤·¤¯¤Ï L<perlunicode/The "Unicode Bug"> ¤ò»²¾È¤·¤Æ¤¯¤À¤µ¤¤¡£)
+¤³¤ÎÍýͳ¤Ë¤è¤ê¡¢¤â¤·¥×¥í¥°¥é¥à¤Ç Unicode ¤ò°·¤¦²ÄǽÀ¤¬¤¢¤ë¤Ê¤é¡¢
+C<use feature 'unicode_strings'> Éû¥×¥é¥°¥Þ¤ò B<¶¯¤¯> ´«¤á¤Þ¤¹¡£
+
+=begin original
+
+This feature is available starting with Perl 5.12; was almost fully
+implemented in Perl 5.14; and extended in Perl 5.16 to cover C<quotemeta>.
+
+=end original
+
+¤³¤Îµ¡Ç½¤Ï Perl 5.12 ¤«¤éÍøÍѲÄǽ¤Ë¤Ê¤ê¤Þ¤·¤¿; Perl 5.14 ¤Ç¤Û¤Ü´°Á´¤Ë
+¼ÂÁõ¤µ¤ì¤Þ¤·¤¿; Perl 5.16 ¤Ç C<quotemeta> ¤ËÂбþ¤¹¤ë¤è¤¦¤Ë³ÈÄ¥¤µ¤ì¤Þ¤·¤¿¡£
+
+=head2 The 'unicode_eval' and 'evalbytes' features
+
+('unicode_eval' ¤È 'evalbytes' µ¡Ç½)
+
+=begin original
+
+Under the C<unicode_eval> feature, Perl's C<eval> function, when passed a
+string, will evaluate it as a string of characters, ignoring any
+C<use utf8> declarations. C<use utf8> exists to declare the encoding of
+the script, which only makes sense for a stream of bytes, not a string of
+characters. Source filters are forbidden, as they also really only make
+sense on strings of bytes. Any attempt to activate a source filter will
+result in an error.
+
+=end original
+
+C<unicode_eval> µ¡Ç½¤Î´ð¤Ç¤Ï¡¢Perl ¤Î C<eval> ´Ø¿ô¤Ëʸ»úÎó¤¬ÅϤµ¤ì¤ë¤È¡¢
+ʸ»ú¤Îʸ»úÎó¤È¤·¤Æɾ²Á¤·¡¢C<use utf8> Àë¸À¤ò̵»ë¤·¤Þ¤¹¡£
+C<use utf8> ¤Ï¥¹¥¯¥ê¥×¥È¤Î¥¨¥ó¥³¡¼¥Ç¥£¥ó¥°¤òÀë¸À¤¹¤ë¤¿¤á¤Ë¸ºß¤·¡¢
+¥Ð¥¤¥È¤ÎʤӤˤΤ߰ÕÌ£¤¬¤¢¤ê¡¢Ê¸»ú¤Îʸ»úÎó¤Ç¤Ï°ÕÌ£¤¬¤¢¤ê¤Þ¤»¤ó¡£
+¥½¡¼¥¹¥Õ¥£¥ë¥¿¤Ï¶Ø»ß¤µ¤ì¤Þ¤¹; ¤³¤ì¤é¤â¥Ð¥¤¥È¤Îʸ»úÎó¤ËÂФ·¤Æ¤Î¤ß
+°ÕÌ£¤¬¤¢¤ë¤«¤é¤Ç¤¹¡£
+¥½¡¼¥¹¥Õ¥£¥ë¥¿¤ò͸ú¤Ë¤·¤è¤¦¤È¤¹¤ë¤¢¤é¤æ¤ë»î¤ß¤Ï¥¨¥é¡¼¤È¤Ê¤ê¤Þ¤¹¡£
+
+=begin original
+
+The C<evalbytes> feature enables the C<evalbytes> keyword, which evaluates
+the argument passed to it as a string of bytes. It dies if the string
+contains any characters outside the 8-bit range. Source filters work
+within C<evalbytes>: they apply to the contents of the string being
+evaluated.
+
+=end original
+
+C<evalbytes> µ¡Ç½¤Ï C<evalbytes> ¥¡¼¥ï¡¼¥É¤ò͸ú¤Ë¤·¤Þ¤¹;
+¤³¤ì¤Ï°ú¿ô¤È¤·¤ÆÅϤµ¤ì¤¿¤â¤Î¤ò¥Ð¥¤¥È¤Îʸ»úÎó¤È¤·¤Æɾ²Á¤·¤Þ¤¹¡£
+ʸ»úÎó¤Ë 8 ¥Ó¥Ã¥È¤ÎÈϰϤγ°Â¦¤Îʸ»ú¤¬´Þ¤Þ¤ì¤Æ¤¤¤ë¤È die ¤·¤Þ¤¹¡£
+¥½¡¼¥¹¥Õ¥£¥ë¥¿¤Ï C<evalbytes> ¤ÎÃæ¤Ç¤ÏÆ°ºî¤·¤Þ¤¹: ¤³¤ì¤é¤Ï
+ɾ²Á¤µ¤ì¤ëʸ»úÎó¤ÎÃæ¿È¤ËÂФ·¤ÆŬÍѤµ¤ì¤Þ¤¹¡£
+
+=begin original
+
+Together, these two features are intended to replace the historical C<eval>
+function, which has (at least) two bugs in it, that cannot easily be fixed
+without breaking existing programs:
+
+=end original
+
+¤³¤ì¤éÆó¤Ä¤Îµ¡Ç½¤Ï¶¦¤Ë¡¢Îò»ËŪ¤Ê C<eval> ´Ø¿ô¤òÃÖ¤´¹¤¨¤ë¤³¤È¤ò
+ÌÜŪ¤È¤·¤Æ¤¤¤Þ¤¹; ¤³¤ì¤Ë¤Ï(¾¯¤Ê¤¯¤È¤â)Æó¤Ä¤Î¥Ð¥°¤¬¤¢¤ê¡¢´û¸¤Î¥×¥í¥°¥é¥à¤ò
+²õ¤¹¤³¤È¤Ê¤¯´Êñ¤Ë½¤Àµ¤¹¤ë¤³¤È¤¬¤Ç¤¤Þ¤»¤ó:
+
+=over
+
+=item *
+
+=begin original
+
+C<eval> behaves differently depending on the internal encoding of the
+string, sometimes treating its argument as a string of bytes, and sometimes
+as a string of characters.
+
+=end original
+
+C<eval> ¤Ïʸ»úÎó²»ÆâÉô¥¨¥ó¥³¡¼¥Ç¥£¥ó¥°¤Ë°Í¸¤·¤Æ°Û¤Ê¤ë¿¶¤ëÉñ¤¤¤ò¹Ô¤¤¡¢
+»þ¤Ë¤Ï°ú¿ô¤ò¥Ð¥¤¥È¤Îʸ»úÎó¤È¤·¤Æ°·¤¤¡¢»þ¤Ë¤Ïʸ»ú¤Îʸ»úÎó¤È¤·¤Æ°·¤¤¤Þ¤¹¡£
+
+=item *
+
+=begin original
+
+Source filters activated within C<eval> leak out into whichever I<file>
+scope is currently being compiled. To give an example with the CPAN module
+L<Semi::Semicolons>:
+
+=end original
+
+C<eval> ¤ÎÃæ¤Ç͸ú¤Ë¤µ¤ì¤¿¥½¡¼¥¹¥Õ¥£¥ë¥¿¤Ï¡¢¤É¤Î I<file> ¥¹¥³¡¼¥×¤¬
+¥³¥ó¥Ñ¥¤¥ë¤µ¤ì¤Æ¤¤¤ë¤«¤Ë¤Ä¤¤¤Æ¥ê¡¼¥¯¤·¤Þ¤¹¡£
+CPAN ¥â¥¸¥å¡¼¥ë¤Ç¤¢¤ë L<Semi::Semicolons> ¤òÎã¤Ë¤·¤Þ¤¹:
+
+ BEGIN { eval "use Semi::Semicolons; # not filtered here " }
+ # filtered here!
+
+=begin original
+
+C<evalbytes> fixes that to work the way one would expect:
+
+=end original
+
+C<evalbytes> ¤Ï¡¢ÁÛÄêÄ̤ê¤ËÆ°ºî¤¹¤ë¤è¤¦¤Ë½¤Àµ¤·¤Þ¤¹:
+
+ use feature "evalbytes";
+ BEGIN { evalbytes "use Semi::Semicolons; # filtered " }
+ # not filtered
+
+=back
+
+=begin original
+
+These two features are available starting with Perl 5.16.
+
+=end original
+
+¤³¤ì¤éÆó¤Ä¤Îµ¡Ç½¤Ï Perl 5.16 ¤«¤éÍøÍѲÄǽ¤Ç¤¹¡£
+
+=head2 The 'current_sub' feature
+
+('current_sub' µ¡Ç½)
+
+=begin original
+
+This provides the C<__SUB__> token that returns a reference to the current
+subroutine or C<undef> outside of a subroutine.
+
+=end original
+
+¤³¤ì¤Ï C<__SUB__> ¥È¡¼¥¯¥ó¤òÄ󶡤·¤Þ¤¹; ¤³¤ì¤Ï¸½ºß¤Î¥µ¥Ö¥ë¡¼¥Á¥ó¤Ø¤Î
+¥ê¥Õ¥¡¥ì¥ó¥¹¤«¡¢¥µ¥Ö¥ë¡¼¥Á¥ó¤Î³°Â¦¤Ç¤Ï C<undef> ¤òÊÖ¤·¤Þ¤¹¡£
+
+=begin original
+
+This feature is available starting with Perl 5.16.
+
+=end original
+
+¤³¤Îµ¡Ç½¤Ï Perl 5.16 ¤«¤éÍøÍѲÄǽ¤Ç¤¹¡£
+
+=head2 The 'array_base' feature
+
+('array_base' µ¡Ç½)
+
+=begin original
+
+This feature supports the legacy C<$[> variable. See L<perlvar/$[> and
+L<arybase>. It is on by default but disabled under C<use v5.16> (see
+L</IMPLICIT LOADING>, below).
+
+=end original
+
+¤³¤Îµ¡Ç½¤Ï¥ì¥¬¥·¡¼¤Ê C<$[> ÊÑ¿ô¤ËÂбþ¤·¤Þ¤¹¡£
+L<perlvar/$[> ¤È L<arybase> ¤ò»²¾È¤·¤Æ¤¯¤À¤µ¤¤¡£
+¤³¤ì¤Ï¥Ç¥Õ¥©¥ë¥È¤Ç¤Ï¥ª¥ó¤Ç¤¹¤¬ C<use v5.16> (¸å½Ò¤Î
+L</IMPLICIT LOADING> »²¾È) ¤Î´ð¤Ç¤Ï̵¸ú¤Ë¤Ê¤ê¤Þ¤¹¡£
+
+=begin original
+
+This feature is available under this name starting with Perl 5.16. In
+previous versions, it was simply on all the time, and this pragma knew
+nothing about it.
+
+=end original
+
+¤³¤Îµ¡Ç½¤Ï Perl 5.16 ¤«¤é¤³¤Î̾Á°¤ÇÍøÍѲÄǽ¤Ç¤¹¡£
+°ÊÁ°¤Î¥Ð¡¼¥¸¥ç¥ó¤Ç¤Ï¡¢Ã±¤Ë¾ï»þŬÍѤµ¤ì¤Æ¤¤¤Æ¡¢¤³¤Î¥×¥é¥°¥Þ¤Ï¤³¤ì¤Ë¤Ä¤¤¤Æ
+²¿¤âÃΤê¤Þ¤»¤ó¤Ç¤·¤¿¡£
+
+=head2 The 'fc' feature
+
+('fc' µ¡Ç½)
+
+=begin original
+
+C<use feature 'fc'> tells the compiler to enable the C<fc> function,
+which implements Unicode casefolding.
+
+=end original
+
+C<use feature 'fc'> ¤Ï¡¢Unicode ¾ö¤ß¹þ¤ß¤ò¼ÂÁõ¤·¤¿ C<fc> ´Ø¿ô¤ò
+͸ú¤Ë¤¹¤ë¤è¤¦¤Ë¥³¥ó¥Ñ¥¤¥é¤ËÅÁ¤¨¤Þ¤¹¡£
+
+=begin original
+
+See L<perlfunc/fc> for details.
+
+=end original
+
+¾Ü¤·¤¯¤Ï L<perlfunc/fc> ¤ò»²¾È¤·¤Æ¤¯¤À¤µ¤¤¡£
+
+=begin original
+
+This feature is available from Perl 5.16 onwards.
+
+=end original
+
+¤³¤Îµ¡Ç½¤Ï Perl 5.16 ¤«¤éÍøÍѲÄǽ¤Ç¤¹¡£
+
+=head2 The 'lexical_subs' feature
+
+('lexical_subs' µ¡Ç½)
+
+=begin original
+
+B<WARNING>: This feature is still experimental and the implementation may
+change in future versions of Perl. For this reason, Perl will
+warn when you use the feature, unless you have explicitly disabled the
+warning:
+
+=end original
+
+B<·Ù¹ð>: ¤³¤Îµ¡Ç½¤Ï¤Þ¤À¼Â¸³Åª¤Ç¡¢¼ÂÁõ¤Ï¾Íè¤Î¥Ð¡¼¥¸¥ç¥ó¤Î Perl ¤Ç
+ÊѤï¤ë¤«¤â¤·¤ì¤Þ¤»¤ó¡£
+¤³¤Î¤¿¤á¡¢¤³¤Îµ¡Ç½¤ò»È¤¦¤È¡¢ÌÀ¼¨Åª¤Ë̵¸ú¤Ë¤·¤Ê¤¤¸Â¤ê·Ù¹ð¤¬È¯À¸¤·¤Þ¤¹:
+
+ no warnings "experimental::lexical_subs";
+
+=begin original
+
+This enables declaration of subroutines via C<my sub foo>, C<state sub foo>
+and C<our sub foo> syntax. See L<perlsub/Lexical Subroutines> for details.
+
+=end original
+
+¤³¤ì¤Ï¡¢C<my sub foo>, C<state sub foo>, C<our sub foo> ʸˡ¤Ë¤è¤ë
+¥µ¥Ö¥ë¡¼¥Á¥ó¤ÎÄêµÁ¤ò͸ú¤Ë¤·¤Þ¤¹¡£
+¾Ü¤·¤¯¤Ï L<perlsub/Lexical Subroutines> ¤ò»²¾È¤·¤Æ¤¯¤À¤µ¤¤¡£
+
+=begin original
+
+This feature is available from Perl 5.18 onwards.
+
+=end original
+
+¤³¤Îµ¡Ç½¤Ï Perl 5.18 ¤«¤éÍøÍѲÄǽ¤Ç¤¹¡£
+
+=head2 The 'postderef' and 'postderef_qq' features
+
+('postderef' ¤È 'postderef_qq' µ¡Ç½)
+
+=begin original
+
+The 'postderef_qq' feature extends the applicability of L<postfix
+dereference syntax|perlref/Postfix Dereference Syntax> so that postfix array
+and scalar dereference are available in double-quotish interpolations. For
+example, it makes the following two statements equivalent:
+
+=end original
+
+'postderef_qq' µ¡Ç½¤Ï¡¢
+L<¸åÃ֥ǥê¥Õ¥¡¥ì¥ó¥¹Ê¸Ë¡|perlref/Postfix Dereference Syntax> ¤Îµ¡Ç½¤ò¡¢
+¸åÃÖÇÛÎó¤È¸åÃÖ¥¹¥«¥é¤Î¥Ç¥ê¥Õ¥¡¥ì¥ó¥¹¤¬¥À¥Ö¥ë¥¯¥©¡¼¥ÈÉ÷ÊÑ¿ôŸ³«¤Ç
+ÍøÍѲÄǽ¤Ë¤Ê¤ë¤è¤¦¤Ë³ÈÄ¥¤·¤Þ¤¹¡£
+Î㤨¤Ð¡¢¼¡¤ÎÆó¤Ä¤Îʸ¤¬Åù²Á¤Ë¤Ê¤ê¤Þ¤¹:
+
+ my $s = "[@{ $h->{a} }]";
+ my $s = "[$h->{a}->@*]";
+
+=begin original
+
+This feature is available from Perl 5.20 onwards. In Perl 5.20 and 5.22, it
+was classed as experimental, and Perl emitted a warning for its
+usage, except when explicitly disabled:
+
+=end original
+
+¤³¤Îµ¡Ç½¤Ï Perl 5.20 ¤«¤éÍøÍѲÄǽ¤Ç¤¹¡£
+Perl 5.20 ¤È 5.22 ¤Ç¤Ï¡¢¤³¤ì¤Ï¼Â¸³Åª¤È°ÌÃ֤Ť±¤é¤ì¤Æ¤¤¤Æ¡¢
+ÌÀ¼¨Åª¤Ë̵¸ú¤Ë¤·¤Ê¤¤¸Â¤ê Perl ¤Ï·Ù¹ð¤ò½ÐÎϤ·¤Æ¤¤¤Þ¤·¤¿:
+
+ no warnings "experimental::postderef";
+
+=begin original
+
+As of Perl 5.24, use of this feature no longer triggers a warning, though
+the C<experimental::postderef> warning category still exists (for
+compatibility with code that disables it).
+
+=end original
+
+Perl 5.24 ¤«¤é¡¢¤³¤Îµ¡Ç½¤Î»ÈÍѤϤâ¤Ï¤ä·Ù¹ð¤ò½ÐÎϤ·¤Ê¤¯¤Ê¤ê¤Þ¤·¤¿¤¬¡¢
+C<experimental::postderef> ·Ù¹ð¥«¥Æ¥´¥ê¤Ï(¤³¤ì¤ò̵¸ú¤Ë¤¹¤ë¥³¡¼¥É¤È¤Î
+¸ß´¹À¤Î¤¿¤á¤Ë)¸ºß¤¹¤ë¤Þ¤Þ¤Ç¤¹¡£
+
+=begin original
+
+The 'postderef' feature was used in Perl 5.20 and Perl 5.22 to enable
+postfix dereference syntax outside double-quotish interpolations. In those
+versions, using it triggered the C<experimental::postderef> warning in the
+same way as the 'postderef_qq' feature did. As of Perl 5.24, this syntax is
+not only no longer experimental, but it is enabled for all Perl code,
+regardless of what feature declarations are in scope.
+
+=end original
+
+'postderef' µ¡Ç½¤Ï¡¢¥À¥Ö¥ë¥¯¥©¡¼¥ÈÉ÷ÊÑ¿ôŸ³«¤Î³°Â¦¤Ç¤Î
+¸åÃ֥ǥê¥Õ¥¡¥ì¥ó¥¹Ê¸Ë¡¤ò͸ú¤Ë¤¹¤ë¤¿¤á¤Ë Perl 5.20 ¤«¤é Perl 5.22 ¤Ç
+»È¤ï¤ì¤Æ¤¤¤Þ¤·¤¿¡£
+¤³¤ì¤é¤Î¥Ð¡¼¥¸¥ç¥ó¤Ç¤Ï¡¢'postderef_qq' µ¡Ç½¤ÈƱÍͤˡ¢¤³¤ì¤ò»È¤¦¤È
+C<experimental::postderef> ·Ù¹ð¤ò°ú¤µ¯¤³¤·¤Þ¤¹¡£
+Perl 5.24 ¤«¤é¡¢¤³¤Îʸˡ¤Ï¤â¤Ï¤ä¼Â¸³Åª¤Ç¤Ï¤Ê¤¯¤Ê¤Ã¤¿¤À¤±¤Ç¤Ï¤Ê¤¯¡¢
+¥¹¥³¡¼¥×Ãæ¤Ç¤É¤ó¤Êµ¡Ç½¤¬Àë¸À¤µ¤ì¤Æ¤¤¤ë¤«¤Ë´Ø¤ï¤é¤º¡¢Á´¤Æ¤Î Perl ¥³¡¼¥É¤Ç
+͸ú¤Ë¤Ê¤ê¤Þ¤·¤¿¡£
+
+=head2 The 'signatures' feature
+
+('signatures' µ¡Ç½)
+
+=begin original
+
+B<WARNING>: This feature is still experimental and the implementation may
+change in future versions of Perl. For this reason, Perl will
+warn when you use the feature, unless you have explicitly disabled the
+warning:
+
+=end original
+
+B<·Ù¹ð>: ¤³¤Îµ¡Ç½¤Ï¤Þ¤À¼Â¸³Åª¤Ç¡¢¼ÂÁõ¤Ï¾Íè¤Î¥Ð¡¼¥¸¥ç¥ó¤Î Perl ¤Ç
+ÊѤï¤ë¤«¤â¤·¤ì¤Þ¤»¤ó¡£
+¤³¤Î¤¿¤á¡¢¤³¤Îµ¡Ç½¤ò»È¤¦¤È¡¢ÌÀ¼¨Åª¤Ë̵¸ú¤Ë¤·¤Ê¤¤¸Â¤ê·Ù¹ð¤¬È¯À¸¤·¤Þ¤¹:
+
+ no warnings "experimental::signatures";
+
+=begin original
+
+This enables unpacking of subroutine arguments into lexical variables
+by syntax such as
+
+=end original
+
+¤³¤ì¤Ï¡¢¼¡¤Î¤è¤¦¤Êʸˡ¤Ë¤è¤Ã¤Æ¥µ¥Ö¥ë¡¼¥Á¥ó¤Î°ú¿ô¤ò¥ì¥¥·¥«¥ëÊÑ¿ô¤Ë
+Ÿ³«¤Ç¤¤ë¤è¤¦¤Ë¤·¤Þ¤¹:
+
+ sub foo ($left, $right) {
+ return $left + $right;
+ }
+
+=begin original
+
+See L<perlsub/Signatures> for details.
+
+=end original
+
+¾Ü¤·¤¯¤Ï L<perlsub/Signatures> ¤ò»²¾È¤·¤Æ¤¯¤À¤µ¤¤¡£
+
+=begin original
+
+This feature is available from Perl 5.20 onwards.
+
+=end original
+
+¤³¤Îµ¡Ç½¤Ï Perl 5.20 ¤«¤éÍøÍѲÄǽ¤Ç¤¹¡£
+
+=head2 The 'refaliasing' feature
+
+('refaliasing' µ¡Ç½)
+
+=begin original
+
+B<WARNING>: This feature is still experimental and the implementation may
+change in future versions of Perl. For this reason, Perl will
+warn when you use the feature, unless you have explicitly disabled the
+warning:
+
+=end original
+
+B<·Ù¹ð>: ¤³¤Îµ¡Ç½¤Ï¤Þ¤À¼Â¸³Åª¤Ç¡¢¼ÂÁõ¤Ï¾Íè¤Î¥Ð¡¼¥¸¥ç¥ó¤Î Perl ¤Ç
+ÊѤï¤ë¤«¤â¤·¤ì¤Þ¤»¤ó¡£
+¤³¤Î¤¿¤á¡¢¤³¤Îµ¡Ç½¤ò»È¤¦¤È¡¢ÌÀ¼¨Åª¤Ë̵¸ú¤Ë¤·¤Ê¤¤¸Â¤ê·Ù¹ð¤¬È¯À¸¤·¤Þ¤¹:
+
+ no warnings "experimental::refaliasing";
+
+=begin original
+
+This enables aliasing via assignment to references:
+
+=end original
+
+¤³¤ì¤Ï¥ê¥Õ¥¡¥ì¥ó¥¹¤Ø¤ÎÂåÆþ¤Ë¤è¤ëÊÌ̾²½¤ò͸ú¤Ë¤·¤Þ¤¹:
+
+ \$a = \$b; # $a and $b now point to the same scalar
+ \@a = \@b; # to the same array
+ \%a = \%b;
+ \&a = \&b;
+ foreach \%hash (@array_of_hash_refs) {
+ ...
+ }
+
+=begin original
+
+See L<perlref/Assigning to References> for details.
+
+=end original
+
+¾Ü¤·¤¯¤Ï L<perlref/Assigning to References> ¤ò»²¾È¤·¤Æ¤¯¤À¤µ¤¤¡£
+
+=begin original
+
+This feature is available from Perl 5.22 onwards.
+
+=end original
+
+¤³¤Îµ¡Ç½¤Ï Perl 5.22 ¤«¤éÍøÍѲÄǽ¤Ç¤¹¡£
+
+=head2 The 'bitwise' feature
+
+('bitwise' µ¡Ç½)
+
+=begin original
+
+B<WARNING>: This feature is still experimental and the implementation may
+change in future versions of Perl. For this reason, Perl will
+warn when you use the feature, unless you have explicitly disabled the
+warning:
+
+=end original
+
+B<·Ù¹ð>: ¤³¤Îµ¡Ç½¤Ï¤Þ¤À¼Â¸³Åª¤Ç¡¢¼ÂÁõ¤Ï¾Íè¤Î¥Ð¡¼¥¸¥ç¥ó¤Î Perl ¤Ç
+ÊѤï¤ë¤«¤â¤·¤ì¤Þ¤»¤ó¡£
+¤³¤Î¤¿¤á¡¢¤³¤Îµ¡Ç½¤ò»È¤¦¤È¡¢ÌÀ¼¨Åª¤Ë̵¸ú¤Ë¤·¤Ê¤¤¸Â¤ê·Ù¹ð¤¬È¯À¸¤·¤Þ¤¹:
+
+ no warnings "experimental::bitwise";
+
+=begin original
+
+This makes the four standard bitwise operators (C<& | ^ ~>) treat their
+operands consistently as numbers, and introduces four new dotted operators
+(C<&. |. ^. ~.>) that treat their operands consistently as strings. The
+same applies to the assignment variants (C<&= |= ^= &.= |.= ^.=>).
+
+=end original
+
+¤³¤ì¤Ï»Í¤Ä¤Îɸ½à¥Ó¥Ã¥Èñ°Ì±é»»»Ò (C<& | ^ ~>) ¤¬¤½¤Î¥ª¥Ú¥é¥ó¥É¤ò
+¿ôÃͤȤ·¤Æ°ì´Ó¤·¤Æ°·¤¦¤è¤¦¤Ë¤Ê¤ê¡¢
+¥ª¥Ú¥é¥ó¥É¤ò°ì´Ó¤·¤Æʸ»úÎó¤È¤·¤Æ°·¤¦¿·¤·¤¤¥É¥Ã¥ÈÉÕ¤±é»»»Ò
+(C<&. |. ^. ~.>) ¤òƳÆþ¤·¤Þ¤¹¡£
+Ʊ¤¸¤â¤Î¤ÏÂåÆþ¤Î°¡¼ï (C<&= |= ^= &.= |.= ^.=>) ¤Ë¤âŬÍѤµ¤ì¤Þ¤¹¡£
+
+=begin original
+
+See L<perlop/Bitwise String Operators> for details.
+
+=end original
+
+¾Ü¤·¤¯¤Ï L<perlop/Bitwise String Operators> ¤ò»²¾È¤·¤Æ¤¯¤À¤µ¤¤¡£
+
+=begin original
+
+This feature is available from Perl 5.22 onwards.
+
+=end original
+
+¤³¤Îµ¡Ç½¤Ï Perl 5.22 ¤«¤éÍøÍѲÄǽ¤Ç¤¹¡£
+
+=head1 FEATURE BUNDLES
+
+(µ¡Ç½¤Î«)
+
+=begin original
+
+It's possible to load multiple features together, using
+a I<feature bundle>. The name of a feature bundle is prefixed with
+a colon, to distinguish it from an actual feature.
+
+=end original
+
+Ê£¿ô¤Îµ¡Ç½¤Î¤Þ¤È¤á¤ÆÆɤ߹þ¤à¤¿¤á¤Ë¤Ï¡¢I<µ¡Ç½¤Î«> (feature bundle) ¤¬
+»È¤¨¤Þ¤¹¡£
+µ¡Ç½¤Î«¤Î̾Á°¤Ë¤Ï¡¢¼ÂºÝ¤Îµ¡Ç½¤È¶èÊ̤¹¤ë¤¿¤á¤Ë¥³¥í¥ó¤¬Á°ÃÖ¤µ¤ì¤Þ¤¹¡£
+
+ use feature ":5.10";
+
+=begin original
+
+The following feature bundles are available:
+
+=end original
+
+°Ê²¼¤Îµ¡Ç½¤Î«¤¬ÍøÍѲÄǽ¤Ç¤¹:
+
+ bundle features included
+ --------- -----------------
+ :default array_base
+
+ :5.10 say state switch array_base
+
+ :5.12 say state switch unicode_strings array_base
+
+ :5.14 say state switch unicode_strings array_base
+
+ :5.16 say state switch unicode_strings
+ unicode_eval evalbytes current_sub fc
+
+ :5.18 say state switch unicode_strings
+ unicode_eval evalbytes current_sub fc
+
+ :5.20 say state switch unicode_strings
+ unicode_eval evalbytes current_sub fc
+
+ :5.22 say state switch unicode_strings
+ unicode_eval evalbytes current_sub fc
+
+ :5.24 say state switch unicode_strings
+ unicode_eval evalbytes current_sub fc
+ postderef_qq
+
+=begin original
+
+The C<:default> bundle represents the feature set that is enabled before
+any C<use feature> or C<no feature> declaration.
+
+=end original
+
+C<:default> «¤Ï¡¢C<use feature> ¤ä C<no feature> Àë¸À¤¬Í¸ú¤Ë¤Ê¤ëÁ°¤Î
+µ¡Ç½½¸¹ç¤òɽ¸½¤·¤Æ¤¤¤Þ¤¹¡£
+
+=begin original
+
+Specifying sub-versions such as the C<0> in C<5.14.0> in feature bundles has
+no effect. Feature bundles are guaranteed to be the same for all sub-versions.
+
+=end original
+
+µ¡Ç½¤Î«¤Ç¤Î C<5.14.0> ¤Î C<0> ¤Î¤è¤¦¤ÊÉû¥Ð¡¼¥¸¥ç¥ó¤ò»ØÄꤷ¤Æ¤â¸ú²Ì¤Ï
+¤¢¤ê¤Þ¤»¤ó¡£
+µ¡Ç½¤Î«¤ÏÁ´¤Æ¤ÎÉû¥Ð¡¼¥¸¥ç¥ó¤Ë´Ø¤·¤ÆƱ¤¸»ö¤¬Êݾڤµ¤ì¤Æ¤¤¤Þ¤¹¡£
+
+ use feature ":5.14.0"; # same as ":5.14"
+ use feature ":5.14.1"; # same as ":5.14"
+
+=head1 IMPLICIT LOADING
+
+(°ÅÌÛ¤ÎÆɤ߹þ¤ß)
+
+=begin original
+
+Instead of loading feature bundles by name, it is easier to let Perl do
+implicit loading of a feature bundle for you.
+
+=end original
+
+µ¡Ç½¤Î«¤ò̾Á°¤ÇÆɤ߹þ¤à¤è¤ê¡¢Perl ¤Ëµ¡Ç½¤Î«¤ò°ÅÌÛ¤ËÆɤ߹þ¤Þ¤»¤ë¤è¤¦¤Ë
+¤·¤¿Êý¤¬´Êñ¤Ç¤¹¡£
+
+=begin original
+
+There are two ways to load the C<feature> pragma implicitly:
+
+=end original
+
+C<feature> ¥×¥é¥°¥Þ¤ò°ÅÌÛ¤ËÆɤ߹þ¤à¤Ë¤ÏÆó¤Ä¤ÎÊýË¡¤¬¤¢¤ê¤Þ¤¹:
+
+=over 4
+
+=item *
+
+=begin original
+
+By using the C<-E> switch on the Perl command-line instead of C<-e>.
+That will enable the feature bundle for that version of Perl in the
+main compilation unit (that is, the one-liner that follows C<-E>).
+
+=end original
+
+Perl ¤Î¥³¥Þ¥ó¥É¥é¥¤¥ó¤Ç C<-e> ¥ª¥×¥·¥ç¥ó¤ÎÂå¤ï¤ê¤Ë C<-E> ¥ª¥×¥·¥ç¥ó¤ò
+»ÈÍѤ·¤¿¾ì¹ç¡£
+¤³¤ì¤Ë¤è¤ê¡¢main ¥³¥ó¥Ñ¥¤¥ëñ°Ì(¤Ä¤Þ¤ê¡¢C<-E> ¤Ë°ú¤Â³¤¯ 1 ¹ÔÌîϺ)¤Ç
+¤½¤Î¥Ð¡¼¥¸¥ç¥ó¤Î Perl ¤Îµ¡Ç½¤Î«¤¬Í¸ú¤Ë¤Ê¤ê¤Þ¤¹¡£
+
+=item *
+
+=begin original
+
+By explicitly requiring a minimum Perl version number for your program, with
+the C<use VERSION> construct. That is,
+
+=end original
+
+C<use VERSION> ¹½Ê¸¤ò»È¤Ã¤Æ¥×¥í¥°¥é¥à¤¬É¬ÍפȤ¹¤ëºÇÄã¸Â¤Î Perl ¥Ð¡¼¥¸¥ç¥ó
+ÈÖ¹æ¤òÌÀ¼¨Åª¤Ë»ØÄꤷ¤¿¾ì¹ç¡£
+¤Ä¤Þ¤ê¡¢°Ê²¼¤Î¤è¤¦¤Ë¤¹¤ë¤È:
+
+ use v5.10.0;
+
+=begin original
+
+will do an implicit
+
+=end original
+
+°ÅÌۤΤ¦¤Á¤Ë°Ê²¼¤Î¤è¤¦¤Ë:
+
+ no feature ':all';
+ use feature ':5.10';
+
+=begin original
+
+and so on. Note how the trailing sub-version
+is automatically stripped from the
+version.
+
+=end original
+
+¤Ê¤ë¤È¤¤¤¦¤³¤È¤Ç¤¹¡£
+ËöÈø¤ÎÉû¥Ð¡¼¥¸¥ç¥ó¤Ï¼«Æ°Åª¤Ë¥Ð¡¼¥¸¥ç¥ó¤«¤é¼è¤ê½ü¤«¤ì¤ë¤è¤¦¤Ë¤Ê¤Ã¤¿¤³¤È¤Ë
+Ãí°Õ¤·¤Æ¤¯¤À¤µ¤¤¡£
+
+=begin original
+
+But to avoid portability warnings (see L<perlfunc/use>), you may prefer:
+
+=end original
+
+¤·¤«¤·°Ü¿¢À¤Î·Ù¹ð(L<perlfunc/use> ¤ò»²¾È¤·¤Æ¤¯¤À¤µ¤¤)¤òÈò¤±¤ë¤¿¤á¤Ë¡¢
+°Ê²¼¤Î¤è¤¦¤Ë¤¹¤ë¤Î¤ò¹¥¤à¤«¤â¤·¤ì¤Þ¤»¤ó:
+
+ use 5.010;
+
+=begin original
+
+with the same effect.
+
+=end original
+
+¤³¤ì¤Ç¤âƱ¤¸¸ú²Ì¤¬ÆÀ¤é¤ì¤Þ¤¹¡£
+
+=begin original
+
+If the required version is older than Perl 5.10, the ":default" feature
+bundle is automatically loaded instead.
+
+=end original
+
+Í׵ᤷ¤¿¥Ð¡¼¥¸¥ç¥ó¤¬ Perl 5.10 ¤è¤êÁ°¤Î¾ì¹ç¡¢Âå¤ï¤ê¤Ëµ¡Ç½¤Î« ":default" ¤¬
+¼«Æ°Åª¤ËÆɤ߹þ¤Þ¤ì¤Þ¤¹¡£
+
+=back
+
+=cut
+
+=begin meta
+
+Translate: SHIRAKATA Kentaro <argra****@ub32*****>
+Status: completed
+
+=end meta
+