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<span class="siteSubtitle">Run on Tue May 4 15:25:55 2010<br />Reported on Tue May 4 15:26:10 2010</span>
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<table>
<tr>
<td class="h" align="right">File</td>
<td align="left">/usr/local/lib/perl5/5.10.1/constant.pm</td>
</tr>
<tr>
<td class="h" align="right">Statements Executed</td>
<td align="left">2002</td>
</tr>
<tr>
<td class="h" align="right">Statement Execution Time</td>
<td align="left">3.66ms</td>
</tr>
</table>
<table id="subs_table" border="1" cellpadding="0" class="tablesorter">
<caption>Subroutines — ordered by exclusive time</caption>
<thead>
<tr>
<th>Calls</th>
<th><span title="Number of Places sub is called from">P</span></th>
<th><span title="Number of Files sub is called from">F</span></th>
<th>Exclusive<br />Time</th>
<th>Inclusive<br />Time</th>
<th>Subroutine</th>
</tr>
</thead>
<tbody>
<tr><td class="c0">86</td><td class="c0">86</td><td class="c0">7</td><td class="c0"><span title="0.2%">2.13ms</span></td><td class="c0"><span title="0.2%">2.58ms</span></td><td class="sub_name"><span style="display: none;">constant::::import</span>constant::<a href="constant-pm-block.html#28">import</a></span></td></tr>
<tr><td class="c0">86</td><td class="c3">1</td><td class="c1">2</td><td class="c0"><span title="0.0%">186µs</span></td><td class="c0"><span title="0.0%">186µs</span></td><td class="sub_name"><span style="display: none;">constant::::CORE:match</span>constant::<a href="constant-pm-block.html#constant__CORE_match">CORE:match</a> (opcode)</span></td></tr>
<tr><td class="c3">1</td><td class="c3">1</td><td class="c3">1</td><td class="c0"><span title="0.0%">84µs</span></td><td class="c3"><span title="0.0%">84µs</span></td><td class="sub_name"><span style="display: none;">constant::::BEGIN@2</span>constant::<a href="constant-pm-block.html#2">BEGIN@2</a></span></td></tr>
<tr><td class="c0">86</td><td class="c3">1</td><td class="c1">2</td><td class="c0"><span title="0.0%">67µs</span></td><td class="c3"><span title="0.0%">67µs</span></td><td class="sub_name"><span style="display: none;">constant::::CORE:regcomp</span>constant::<a href="constant-pm-block.html#constant__CORE_regcomp">CORE:regcomp</a> (opcode)</span></td></tr>
<tr><td class="c3">1</td><td class="c3">1</td><td class="c3">1</td><td class="c3"><span title="0.0%">13µs</span></td><td class="c3"><span title="0.0%">18µs</span></td><td class="sub_name"><span style="display: none;">constant::::BEGIN@3</span>constant::<a href="constant-pm-block.html#3">BEGIN@3</a></span></td></tr>
<tr><td class="c3">1</td><td class="c3">1</td><td class="c3">1</td><td class="c3"><span title="0.0%">11µs</span></td><td class="c2"><span title="0.0%">100µs</span></td><td class="sub_name"><span style="display: none;">constant::::BEGIN@4</span>constant::<a href="constant-pm-block.html#4">BEGIN@4</a></span></td></tr>
<tr><td class="c3">1</td><td class="c3">1</td><td class="c3">1</td><td class="c3"><span title="0.0%">10µs</span></td><td class="c3"><span title="0.0%">63µs</span></td><td class="sub_name"><span style="display: none;">constant::::BEGIN@6</span>constant::<a href="constant-pm-block.html#6">BEGIN@6</a></span></td></tr>
<tr><td class="c3">1</td><td class="c3">1</td><td class="c3">1</td><td class="c3"><span title="0.0%">9µs</span></td><td class="c3"><span title="0.0%">30µs</span></td><td class="sub_name"><span style="display: none;">constant::::BEGIN@38</span>constant::<a href="constant-pm-block.html#38">BEGIN@38</a></span></td></tr>
<tr><td class="c3">1</td><td class="c3">1</td><td class="c3">1</td><td class="c3"><span title="0.0%">9µs</span></td><td class="c3"><span title="0.0%">24µs</span></td><td class="sub_name"><span style="display: none;">constant::::BEGIN@101</span>constant::<a href="constant-pm-block.html#101">BEGIN@101</a></span></td></tr>
<tr><td class="c3">0</td><td class="c3">0</td><td class="c3">0</td><td class="c3"><span title="0.0%">0s</span></td><td class="c3"><span title="0.0%">0s</span></td><td class="sub_name"><span style="display: none;">constant::::__ANON__[:115]</span>constant::<a href="constant-pm-block.html#115">__ANON__[:115]</a></span></td></tr>
<tr><td class="c3">0</td><td class="c3">0</td><td class="c3">0</td><td class="c3"><span title="0.0%">0s</span></td><td class="c3"><span title="0.0%">0s</span></td><td class="sub_name"><span style="display: none;">constant::::__ANON__[:119]</span>constant::<a href="constant-pm-block.html#119">__ANON__[:119]</a></span></td></tr>
<tr><td class="c3">0</td><td class="c3">0</td><td class="c3">0</td><td class="c3"><span title="0.0%">0s</span></td><td class="c3"><span title="0.0%">0s</span></td><td class="sub_name"><span style="display: none;">constant::::__ANON__[:121]</span>constant::<a href="constant-pm-block.html#121">__ANON__[:121]</a></span></td></tr>
</tbody>
</table>
Call graph for these subroutines as a <a href="http://en.wikipedia.org/wiki/Graphviz">Graphviz</a> <a href="usr-local-lib-perl5-5-10-1-constant-pm.dot">dot language file</a>.
<table border="1" cellpadding="0">
<thead>
<tr><th>Line</th>
<th><span title="Number of statements executed">State<br />ments</span></th>
<th><span title="Time spend executing statements on the line,
excluding time spent executing statements in any called subroutines">Time<br />on line</span></th>
<th><span title="Number of subroutines calls">Calls</span></th>
<th><span title="Time spent in subroutines called">Time<br />in subs</span></th>
<th class="left_indent_header">Code</th>
</tr>
</thead>
<tbody>
<tr><td class="h"><a name="1"></a>1</td><td></td><td></td><td></td><td></td><td class="s">package constant;</td></tr>
<tr><td class="h"><a name="2"></a>2</td><td class="c3">3</td><td class="c3"><span title="Avg 35µs">106µs</span></td><td class="c3">1</td><td class="c3">84µs</td><td class="s"><div class="calls"><div class="calls_in"># spent 84µs within constant::BEGIN@2 which was called
# once (84µs+0s) by Class::MOP::Method::Generated::BEGIN@15 at <a href="constant-pm-block.html#2">line 2</a></div></div>use 5.005;<div class="calls"><div class="calls_out"># spent 84µs making 1 call to <a href="constant-pm-block.html#2">constant::BEGIN@2</a></div></div></td></tr>
<tr><td class="h"><a name="3"></a>3</td><td class="c3">3</td><td class="c3"><span title="Avg 11µs">34µs</span></td><td class="c3">2</td><td class="c3">22µs</td><td class="s"><div class="calls"><div class="calls_in"># spent 18µs (13+5) within constant::BEGIN@3 which was called
# once (13µs+5µs) by Class::MOP::Method::Generated::BEGIN@15 at <a href="constant-pm-block.html#3">line 3</a></div></div>use strict;<div class="calls"><div class="calls_out"># spent 18µs making 1 call to <a href="constant-pm-block.html#3">constant::BEGIN@3</a>
# spent 5µs making 1 call to <a href="strict-pm-block.html#34">strict::import</a></div></div></td></tr>
<tr><td class="h"><a name="4"></a>4</td><td class="c3">3</td><td class="c3"><span title="Avg 18µs">54µs</span></td><td class="c3">2</td><td class="c0">189µs</td><td class="s"><div class="calls"><div class="calls_in"># spent 100µs (11+89) within constant::BEGIN@4 which was called
# once (11µs+89µs) by Class::MOP::Method::Generated::BEGIN@15 at <a href="constant-pm-block.html#4">line 4</a></div></div>use warnings::register;<div class="calls"><div class="calls_out"># spent 100µs making 1 call to <a href="constant-pm-block.html#4">constant::BEGIN@4</a>
# spent 89µs making 1 call to <a href="warnings-register-pm-block.html#36">warnings::register::import</a></div></div></td></tr>
<tr><td class="h"><a name="5"></a>5</td><td></td><td></td><td></td><td></td><td class="s"></td></tr>
<tr><td class="h"><a name="6"></a>6</td><td class="c3">3</td><td class="c2"><span title="Avg 52µs">156µs</span></td><td class="c3">2</td><td class="c2">116µs</td><td class="s"><div class="calls"><div class="calls_in"># spent 63µs (10+53) within constant::BEGIN@6 which was called
# once (10µs+53µs) by Class::MOP::Method::Generated::BEGIN@15 at <a href="constant-pm-block.html#6">line 6</a></div></div>use vars qw($VERSION %declared);<div class="calls"><div class="calls_out"># spent 63µs making 1 call to <a href="constant-pm-block.html#6">constant::BEGIN@6</a>
# spent 53µs making 1 call to <a href="vars-pm-block.html#10">vars::import</a></div></div></td></tr>
<tr><td class="h"><a name="7"></a>7</td><td class="c3">1</td><td class="c3"><span title="Avg 1µs">1µs</span></td><td></td><td></td><td class="s">$VERSION = '1.17';</td></tr>
<tr><td class="h"><a name="8"></a>8</td><td></td><td></td><td></td><td></td><td class="s"></td></tr>
<tr><td class="h"><a name="9"></a>9</td><td></td><td></td><td></td><td></td><td class="s">#=======================================================================</td></tr>
<tr><td class="h"><a name="10"></a>10</td><td></td><td></td><td></td><td></td><td class="s"></td></tr>
<tr><td class="h"><a name="11"></a>11</td><td></td><td></td><td></td><td></td><td class="s"># Some names are evil choices.</td></tr>
<tr><td class="h"><a name="12"></a>12</td><td class="c3">1</td><td class="c3"><span title="Avg 8µs">8µs</span></td><td></td><td></td><td class="s">my %keywords = map +($_, 1), qw{ BEGIN INIT CHECK END DESTROY AUTOLOAD };</td></tr>
<tr><td class="h"><a name="13"></a>13</td><td class="c3">1</td><td class="c3"><span title="Avg 2µs">2µs</span></td><td></td><td></td><td class="s">$keywords{UNITCHECK}++ if $] > 5.009;</td></tr>
<tr><td class="h"><a name="14"></a>14</td><td></td><td></td><td></td><td></td><td class="s"></td></tr>
<tr><td class="h"><a name="15"></a>15</td><td class="c3">1</td><td class="c3"><span title="Avg 7µs">7µs</span></td><td></td><td></td><td class="s">my %forced_into_main = map +($_, 1),</td></tr>
<tr><td class="h"><a name="16"></a>16</td><td></td><td></td><td></td><td></td><td class="s"> qw{ STDIN STDOUT STDERR ARGV ARGVOUT ENV INC SIG };</td></tr>
<tr><td class="h"><a name="17"></a>17</td><td></td><td></td><td></td><td></td><td class="s"></td></tr>
<tr><td class="h"><a name="18"></a>18</td><td class="c3">1</td><td class="c3"><span title="Avg 7µs">7µs</span></td><td></td><td></td><td class="s">my %forbidden = (%keywords, %forced_into_main);</td></tr>
<tr><td class="h"><a name="19"></a>19</td><td></td><td></td><td></td><td></td><td class="s"></td></tr>
<tr><td class="h"><a name="20"></a>20</td><td></td><td></td><td></td><td></td><td class="s">#=======================================================================</td></tr>
<tr><td class="h"><a name="21"></a>21</td><td></td><td></td><td></td><td></td><td class="s"># import() - import symbols into user's namespace</td></tr>
<tr><td class="h"><a name="22"></a>22</td><td></td><td></td><td></td><td></td><td class="s">#</td></tr>
<tr><td class="h"><a name="23"></a>23</td><td></td><td></td><td></td><td></td><td class="s"># What we actually do is define a function in the caller's namespace</td></tr>
<tr><td class="h"><a name="24"></a>24</td><td></td><td></td><td></td><td></td><td class="s"># which returns the value. The function we create will normally</td></tr>
<tr><td class="h"><a name="25"></a>25</td><td></td><td></td><td></td><td></td><td class="s"># be inlined as a constant, thereby avoiding further sub calling </td></tr>
<tr><td class="h"><a name="26"></a>26</td><td></td><td></td><td></td><td></td><td class="s"># overhead.</td></tr>
<tr><td class="h"><a name="27"></a>27</td><td></td><td></td><td></td><td></td><td class="s">#=======================================================================</td></tr>
<tr><td class="h"><a name="28"></a>28</td><td></td><td></td><td></td><td></td><td class="s"><div class="calls"><div class="calls_in"># spent 2.58ms (2.13+453µs) within constant::import which was called 86 times, avg 30µs/call:
# once (48µs+36µs) by Class::MOP::Method::Generated::BEGIN@15 at <a href="Class-MOP-Method-Generated-pm-block.html#15">line 15 of Class/MOP/Method/Generated.pm</a>
# once (57µs+11µs) by Compress::Raw::Zlib::BEGIN@86 at <a href="Compress-Raw-Zlib-pm-block.html#86">line 86 of Compress/Raw/Zlib.pm</a>
# once (62µs+5µs) by IO::Compress::Base::Common::BEGIN@473 at <a href="IO-Compress-Base-Common-pm-block.html#473">line 473 of IO/Compress/Base/Common.pm</a>
# once (46µs+9µs) by URI::_punycode::BEGIN@14 at <a href="URI-_punycode-pm-block.html#14">line 14 of URI/_punycode.pm</a>
# once (40µs+11µs) by IO::Compress::Gzip::Constants::BEGIN@65 at <a href="IO-Compress-Gzip-Constants-pm-block.html#65">line 65 of IO/Compress/Gzip/Constants.pm</a>
# once (40µs+10µs) by Time::Local::BEGIN@28 at <a href="Time-Local-pm-block.html#28">line 28 of Time/Local.pm</a>
# once (42µs+8µs) by Compress::Raw::Zlib::BEGIN@70 at <a href="Compress-Raw-Zlib-pm-block.html#70">line 70 of Compress/Raw/Zlib.pm</a>
# once (39µs+11µs) by IO::Compress::Base::Common::BEGIN@41 at <a href="IO-Compress-Base-Common-pm-block.html#41">line 41 of IO/Compress/Base/Common.pm</a>
# once (38µs+7µs) by IO::Compress::Gzip::Constants::BEGIN@76 at <a href="IO-Compress-Gzip-Constants-pm-block.html#76">line 76 of IO/Compress/Gzip/Constants.pm</a>
# once (36µs+6µs) by IO::Compress::Gzip::Constants::BEGIN@77 at <a href="IO-Compress-Gzip-Constants-pm-block.html#77">line 77 of IO/Compress/Gzip/Constants.pm</a>
# once (33µs+6µs) by IO::Compress::Base::Common::BEGIN@463 at <a href="IO-Compress-Base-Common-pm-block.html#463">line 463 of IO/Compress/Base/Common.pm</a>
# once (32µs+5µs) by Compress::Raw::Zlib::BEGIN@110 at <a href="Compress-Raw-Zlib-pm-block.html#110">line 110 of Compress/Raw/Zlib.pm</a>
# once (29µs+5µs) by IO::Compress::Gzip::Constants::BEGIN@67 at <a href="IO-Compress-Gzip-Constants-pm-block.html#67">line 67 of IO/Compress/Gzip/Constants.pm</a>
# once (28µs+7µs) by IO::Compress::Base::Common::BEGIN@461 at <a href="IO-Compress-Base-Common-pm-block.html#461">line 461 of IO/Compress/Base/Common.pm</a>
# once (28µs+4µs) by IO::Compress::Base::Common::BEGIN@464 at <a href="IO-Compress-Base-Common-pm-block.html#464">line 464 of IO/Compress/Base/Common.pm</a>
# once (26µs+6µs) by IO::Compress::Base::Common::BEGIN@42 at <a href="IO-Compress-Base-Common-pm-block.html#42">line 42 of IO/Compress/Base/Common.pm</a>
# once (25µs+7µs) by IO::Compress::Base::Common::BEGIN@131 at <a href="IO-Compress-Base-Common-pm-block.html#131">line 131 of IO/Compress/Base/Common.pm</a>
# once (25µs+6µs) by IO::Compress::Base::Common::BEGIN@130 at <a href="IO-Compress-Base-Common-pm-block.html#130">line 130 of IO/Compress/Base/Common.pm</a>
# once (26µs+4µs) by IO::Compress::Gzip::Constants::BEGIN@115 at <a href="IO-Compress-Gzip-Constants-pm-block.html#115">line 115 of IO/Compress/Gzip/Constants.pm</a>
# once (26µs+4µs) by U64::BEGIN@820 at <a href="IO-Compress-Base-Common-pm-block.html#820">line 820 of IO/Compress/Base/Common.pm</a>
# once (26µs+5µs) by IO::Compress::Gzip::Constants::BEGIN@73 at <a href="IO-Compress-Gzip-Constants-pm-block.html#73">line 73 of IO/Compress/Gzip/Constants.pm</a>
# once (26µs+4µs) by Compress::Raw::Zlib::BEGIN@102 at <a href="Compress-Raw-Zlib-pm-block.html#102">line 102 of Compress/Raw/Zlib.pm</a>
# once (24µs+5µs) by U64::BEGIN@818 at <a href="IO-Compress-Base-Common-pm-block.html#818">line 818 of IO/Compress/Base/Common.pm</a>
# once (24µs+5µs) by IO::Compress::Gzip::Constants::BEGIN@66 at <a href="IO-Compress-Gzip-Constants-pm-block.html#66">line 66 of IO/Compress/Gzip/Constants.pm</a>
# once (25µs+4µs) by Compress::Raw::Zlib::BEGIN@71 at <a href="Compress-Raw-Zlib-pm-block.html#71">line 71 of Compress/Raw/Zlib.pm</a>
# once (23µs+6µs) by IO::Compress::Base::Common::BEGIN@132 at <a href="IO-Compress-Base-Common-pm-block.html#132">line 132 of IO/Compress/Base/Common.pm</a>
# once (25µs+4µs) by URI::_punycode::BEGIN@16 at <a href="URI-_punycode-pm-block.html#16">line 16 of URI/_punycode.pm</a>
# once (25µs+4µs) by URI::_punycode::BEGIN@20 at <a href="URI-_punycode-pm-block.html#20">line 20 of URI/_punycode.pm</a>
# once (24µs+5µs) by IO::Compress::Base::Common::BEGIN@43 at <a href="IO-Compress-Base-Common-pm-block.html#43">line 43 of IO/Compress/Base/Common.pm</a>
# once (23µs+5µs) by IO::Uncompress::Base::BEGIN@14 at <a href="IO-Uncompress-Base-pm-block.html#14">line 14 of IO/Uncompress/Base.pm</a>
# once (23µs+5µs) by IO::Compress::Gzip::Constants::BEGIN@89 at <a href="IO-Compress-Gzip-Constants-pm-block.html#89">line 89 of IO/Compress/Gzip/Constants.pm</a>
# once (23µs+5µs) by Compress::Raw::Zlib::BEGIN@83 at <a href="Compress-Raw-Zlib-pm-block.html#83">line 83 of Compress/Raw/Zlib.pm</a>
# once (23µs+5µs) by IO::Compress::Gzip::Constants::BEGIN@78 at <a href="IO-Compress-Gzip-Constants-pm-block.html#78">line 78 of IO/Compress/Gzip/Constants.pm</a>
# once (23µs+5µs) by IO::Compress::Gzip::Constants::BEGIN@143 at <a href="IO-Compress-Gzip-Constants-pm-block.html#143">line 143 of IO/Compress/Gzip/Constants.pm</a>
# once (23µs+4µs) by Compress::Raw::Zlib::BEGIN@106 at <a href="Compress-Raw-Zlib-pm-block.html#106">line 106 of Compress/Raw/Zlib.pm</a>
# once (22µs+5µs) by IO::Compress::Gzip::Constants::BEGIN@87 at <a href="IO-Compress-Gzip-Constants-pm-block.html#87">line 87 of IO/Compress/Gzip/Constants.pm</a>
# once (22µs+5µs) by IO::Compress::Gzip::Constants::BEGIN@80 at <a href="IO-Compress-Gzip-Constants-pm-block.html#80">line 80 of IO/Compress/Gzip/Constants.pm</a>
# once (22µs+4µs) by Compress::Raw::Zlib::BEGIN@111 at <a href="Compress-Raw-Zlib-pm-block.html#111">line 111 of Compress/Raw/Zlib.pm</a>
# once (22µs+4µs) by IO::Compress::Base::Common::BEGIN@134 at <a href="IO-Compress-Base-Common-pm-block.html#134">line 134 of IO/Compress/Base/Common.pm</a>
# once (22µs+5µs) by IO::Compress::Base::Common::BEGIN@462 at <a href="IO-Compress-Base-Common-pm-block.html#462">line 462 of IO/Compress/Base/Common.pm</a>
# once (22µs+5µs) by IO::Compress::Gzip::Constants::BEGIN@109 at <a href="IO-Compress-Gzip-Constants-pm-block.html#109">line 109 of IO/Compress/Gzip/Constants.pm</a>
# once (22µs+4µs) by IO::Compress::Gzip::Constants::BEGIN@69 at <a href="IO-Compress-Gzip-Constants-pm-block.html#69">line 69 of IO/Compress/Gzip/Constants.pm</a>
# once (22µs+4µs) by IO::Compress::Gzip::Constants::BEGIN@90 at <a href="IO-Compress-Gzip-Constants-pm-block.html#90">line 90 of IO/Compress/Gzip/Constants.pm</a>
# once (22µs+4µs) by Compress::Raw::Zlib::BEGIN@108 at <a href="Compress-Raw-Zlib-pm-block.html#108">line 108 of Compress/Raw/Zlib.pm</a>
# once (22µs+4µs) by IO::Compress::Gzip::Constants::BEGIN@70 at <a href="IO-Compress-Gzip-Constants-pm-block.html#70">line 70 of IO/Compress/Gzip/Constants.pm</a>
# once (22µs+4µs) by IO::Compress::Gzip::Constants::BEGIN@84 at <a href="IO-Compress-Gzip-Constants-pm-block.html#84">line 84 of IO/Compress/Gzip/Constants.pm</a>
# once (21µs+5µs) by IO::Compress::Gzip::Constants::BEGIN@119 at <a href="IO-Compress-Gzip-Constants-pm-block.html#119">line 119 of IO/Compress/Gzip/Constants.pm</a>
# once (21µs+4µs) by IO::Compress::Gzip::Constants::BEGIN@75 at <a href="IO-Compress-Gzip-Constants-pm-block.html#75">line 75 of IO/Compress/Gzip/Constants.pm</a>
# once (21µs+4µs) by IO::Compress::Gzip::Constants::BEGIN@82 at <a href="IO-Compress-Gzip-Constants-pm-block.html#82">line 82 of IO/Compress/Gzip/Constants.pm</a>
# once (21µs+4µs) by IO::Compress::Gzip::Constants::BEGIN@86 at <a href="IO-Compress-Gzip-Constants-pm-block.html#86">line 86 of IO/Compress/Gzip/Constants.pm</a>
# once (21µs+4µs) by URI::_punycode::BEGIN@15 at <a href="URI-_punycode-pm-block.html#15">line 15 of URI/_punycode.pm</a>
# once (21µs+4µs) by IO::Compress::Gzip::Constants::BEGIN@88 at <a href="IO-Compress-Gzip-Constants-pm-block.html#88">line 88 of IO/Compress/Gzip/Constants.pm</a>
# once (21µs+4µs) by Compress::Raw::Zlib::BEGIN@101 at <a href="Compress-Raw-Zlib-pm-block.html#101">line 101 of Compress/Raw/Zlib.pm</a>
# once (21µs+4µs) by Compress::Raw::Zlib::BEGIN@87 at <a href="Compress-Raw-Zlib-pm-block.html#87">line 87 of Compress/Raw/Zlib.pm</a>
# once (21µs+4µs) by Compress::Raw::Zlib::BEGIN@85 at <a href="Compress-Raw-Zlib-pm-block.html#85">line 85 of Compress/Raw/Zlib.pm</a>
# once (21µs+4µs) by IO::Compress::Gzip::Constants::BEGIN@74 at <a href="IO-Compress-Gzip-Constants-pm-block.html#74">line 74 of IO/Compress/Gzip/Constants.pm</a>
# once (21µs+4µs) by IO::Compress::Base::Common::BEGIN@474 at <a href="IO-Compress-Base-Common-pm-block.html#474">line 474 of IO/Compress/Base/Common.pm</a>
# once (21µs+4µs) by Compress::Raw::Zlib::BEGIN@115 at <a href="Compress-Raw-Zlib-pm-block.html#115">line 115 of Compress/Raw/Zlib.pm</a>
# once (20µs+4µs) by IO::Compress::Base::Common::BEGIN@44 at <a href="IO-Compress-Base-Common-pm-block.html#44">line 44 of IO/Compress/Base/Common.pm</a>
# once (21µs+4µs) by Compress::Raw::Zlib::BEGIN@112 at <a href="Compress-Raw-Zlib-pm-block.html#112">line 112 of Compress/Raw/Zlib.pm</a>
# once (20µs+4µs) by IO::Compress::Gzip::Constants::BEGIN@113 at <a href="IO-Compress-Gzip-Constants-pm-block.html#113">line 113 of IO/Compress/Gzip/Constants.pm</a>
# once (20µs+4µs) by IO::Compress::Base::Common::BEGIN@465 at <a href="IO-Compress-Base-Common-pm-block.html#465">line 465 of IO/Compress/Base/Common.pm</a>
# once (20µs+4µs) by Compress::Raw::Zlib::BEGIN@114 at <a href="Compress-Raw-Zlib-pm-block.html#114">line 114 of Compress/Raw/Zlib.pm</a>
# once (20µs+4µs) by Compress::Raw::Zlib::BEGIN@84 at <a href="Compress-Raw-Zlib-pm-block.html#84">line 84 of Compress/Raw/Zlib.pm</a>
# once (20µs+4µs) by IO::Compress::Base::Common::BEGIN@476 at <a href="IO-Compress-Base-Common-pm-block.html#476">line 476 of IO/Compress/Base/Common.pm</a>
# once (20µs+4µs) by IO::Compress::Base::Common::BEGIN@471 at <a href="IO-Compress-Base-Common-pm-block.html#471">line 471 of IO/Compress/Base/Common.pm</a>
# once (20µs+4µs) by IO::Compress::Gzip::Constants::BEGIN@92 at <a href="IO-Compress-Gzip-Constants-pm-block.html#92">line 92 of IO/Compress/Gzip/Constants.pm</a>
# once (20µs+4µs) by Time::Local::BEGIN@29 at <a href="Time-Local-pm-block.html#29">line 29 of Time/Local.pm</a>
# once (20µs+4µs) by IO::Uncompress::Base::BEGIN@15 at <a href="IO-Uncompress-Base-pm-block.html#15">line 15 of IO/Uncompress/Base.pm</a>
# once (20µs+4µs) by Compress::Raw::Zlib::BEGIN@113 at <a href="Compress-Raw-Zlib-pm-block.html#113">line 113 of Compress/Raw/Zlib.pm</a>
# once (20µs+4µs) by IO::Compress::Gzip::Constants::BEGIN@111 at <a href="IO-Compress-Gzip-Constants-pm-block.html#111">line 111 of IO/Compress/Gzip/Constants.pm</a>
# once (20µs+4µs) by URI::_punycode::BEGIN@18 at <a href="URI-_punycode-pm-block.html#18">line 18 of URI/_punycode.pm</a>
# once (20µs+4µs) by IO::Compress::Base::Common::BEGIN@466 at <a href="IO-Compress-Base-Common-pm-block.html#466">line 466 of IO/Compress/Base/Common.pm</a>
# once (20µs+4µs) by IO::Compress::Base::Common::BEGIN@470 at <a href="IO-Compress-Base-Common-pm-block.html#470">line 470 of IO/Compress/Base/Common.pm</a>
# once (19µs+4µs) by Compress::Raw::Zlib::BEGIN@103 at <a href="Compress-Raw-Zlib-pm-block.html#103">line 103 of Compress/Raw/Zlib.pm</a>
# once (19µs+4µs) by U64::BEGIN@819 at <a href="IO-Compress-Base-Common-pm-block.html#819">line 819 of IO/Compress/Base/Common.pm</a>
# once (19µs+4µs) by Compress::Raw::Zlib::BEGIN@105 at <a href="Compress-Raw-Zlib-pm-block.html#105">line 105 of Compress/Raw/Zlib.pm</a>
# once (19µs+4µs) by IO::Compress::Gzip::Constants::BEGIN@114 at <a href="IO-Compress-Gzip-Constants-pm-block.html#114">line 114 of IO/Compress/Gzip/Constants.pm</a>
# once (19µs+4µs) by URI::_punycode::BEGIN@17 at <a href="URI-_punycode-pm-block.html#17">line 17 of URI/_punycode.pm</a>
# once (19µs+4µs) by IO::Compress::Base::Common::BEGIN@469 at <a href="IO-Compress-Base-Common-pm-block.html#469">line 469 of IO/Compress/Base/Common.pm</a>
# once (19µs+4µs) by Time::Local::BEGIN@30 at <a href="Time-Local-pm-block.html#30">line 30 of Time/Local.pm</a>
# once (19µs+4µs) by IO::Compress::Base::Common::BEGIN@475 at <a href="IO-Compress-Base-Common-pm-block.html#475">line 475 of IO/Compress/Base/Common.pm</a>
# once (19µs+4µs) by Compress::Raw::Zlib::BEGIN@104 at <a href="Compress-Raw-Zlib-pm-block.html#104">line 104 of Compress/Raw/Zlib.pm</a>
# once (19µs+4µs) by URI::_punycode::BEGIN@19 at <a href="URI-_punycode-pm-block.html#19">line 19 of URI/_punycode.pm</a>
# once (19µs+4µs) by IO::Compress::Base::Common::BEGIN@477 at <a href="IO-Compress-Base-Common-pm-block.html#477">line 477 of IO/Compress/Base/Common.pm</a>
# once (19µs+4µs) by IO::Compress::Base::Common::BEGIN@478 at <a href="IO-Compress-Base-Common-pm-block.html#478">line 478 of IO/Compress/Base/Common.pm</a></div></div>sub import {</td></tr>
<tr><td class="h"><a name="29"></a>29</td><td class="c0">860</td><td class="c0"><span title="Avg 769ns">661µs</span></td><td></td><td></td><td class="s"> my $class = shift;</td></tr>
<tr><td class="h"><a name="30"></a>30</td><td></td><td></td><td></td><td></td><td class="s"> return unless @_; # Ignore 'use constant;'</td></tr>
<tr><td class="h"><a name="31"></a>31</td><td></td><td></td><td></td><td></td><td class="s"> my $constants;</td></tr>
<tr><td class="h"><a name="32"></a>32</td><td></td><td></td><td></td><td></td><td class="s"> my $multiple = ref $_[0];</td></tr>
<tr><td class="h"><a name="33"></a>33</td><td></td><td></td><td></td><td></td><td class="s"> my $pkg = caller;</td></tr>
<tr><td class="h"><a name="34"></a>34</td><td></td><td></td><td></td><td></td><td class="s"> my $symtab;</td></tr>
<tr><td class="h"><a name="35"></a>35</td><td></td><td></td><td></td><td></td><td class="s"> my $str_end = $] >= 5.006 ? "\\z" : "\\Z";</td></tr>
<tr><td class="h"><a name="36"></a>36</td><td></td><td></td><td></td><td></td><td class="s"></td></tr>
<tr><td class="h"><a name="37"></a>37</td><td class="c0">86</td><td class="c3"><span title="Avg 1µs">108µs</span></td><td></td><td></td><td class="s"> if ($] > 5.009002) {</td></tr>
<tr><td class="h"><a name="38"></a>38</td><td class="c3">3</td><td class="c0"><span title="Avg 109µs">327µs</span></td><td class="c3">2</td><td class="c3">51µs</td><td class="s"><div class="calls"><div class="calls_in"># spent 30µs (9+21) within constant::BEGIN@38 which was called
# once (9µs+21µs) by Class::MOP::Method::Generated::BEGIN@15 at <a href="constant-pm-block.html#38">line 38</a></div></div> no strict 'refs';<div class="calls"><div class="calls_out"> # spent 30µs making 1 call to <a href="constant-pm-block.html#38">constant::BEGIN@38</a>
# spent 21µs making 1 call to <a href="strict-pm-block.html#39">strict::unimport</a></div></div></td></tr>
<tr><td class="h"><a name="39"></a>39</td><td></td><td></td><td></td><td></td><td class="s"> $symtab = \%{$pkg . '::'};</td></tr>
<tr><td class="h"><a name="40"></a>40</td><td></td><td></td><td></td><td></td><td class="s"> };</td></tr>
<tr><td class="h"><a name="41"></a>41</td><td></td><td></td><td></td><td></td><td class="s"></td></tr>
<tr><td class="h"><a name="42"></a>42</td><td class="c0">86</td><td class="c3"><span title="Avg 2µs">131µs</span></td><td></td><td></td><td class="s"> if ( $multiple ) {</td></tr>
<tr><td class="h"><a name="43"></a>43</td><td></td><td></td><td></td><td></td><td class="s"> if (ref $_[0] ne 'HASH') {</td></tr>
<tr><td class="h"><a name="44"></a>44</td><td></td><td></td><td></td><td></td><td class="s"> require Carp;</td></tr>
<tr><td class="h"><a name="45"></a>45</td><td></td><td></td><td></td><td></td><td class="s"> Carp::croak("Invalid reference type '".ref(shift)."' not 'HASH'");</td></tr>
<tr><td class="h"><a name="46"></a>46</td><td></td><td></td><td></td><td></td><td class="s"> }</td></tr>
<tr><td class="h"><a name="47"></a>47</td><td></td><td></td><td></td><td></td><td class="s"> $constants = shift;</td></tr>
<tr><td class="h"><a name="48"></a>48</td><td></td><td></td><td></td><td></td><td class="s"> } else {</td></tr>
<tr><td class="h"><a name="49"></a>49</td><td></td><td></td><td></td><td></td><td class="s"> $constants->{+shift} = undef;</td></tr>
<tr><td class="h"><a name="50"></a>50</td><td></td><td></td><td></td><td></td><td class="s"> }</td></tr>
<tr><td class="h"><a name="51"></a>51</td><td></td><td></td><td></td><td></td><td class="s"></td></tr>
<tr><td class="h"><a name="52"></a>52</td><td></td><td></td><td></td><td></td><td class="s"> foreach my $name ( keys %$constants ) {</td></tr>
<tr><td class="h"><a name="53"></a>53</td><td class="c0">258</td><td class="c0"><span title="Avg 3µs">741µs</span></td><td></td><td></td><td class="s"> unless (defined $name) {</td></tr>
<tr><td class="h"><a name="54"></a>54</td><td></td><td></td><td></td><td></td><td class="s"> require Carp;</td></tr>
<tr><td class="h"><a name="55"></a>55</td><td></td><td></td><td></td><td></td><td class="s"> Carp::croak("Can't use undef as constant name");</td></tr>
<tr><td class="h"><a name="56"></a>56</td><td></td><td></td><td></td><td></td><td class="s"> }</td></tr>
<tr><td class="h"><a name="57"></a>57</td><td></td><td></td><td></td><td></td><td class="s"></td></tr>
<tr><td class="h"><a name="58"></a>58</td><td></td><td></td><td></td><td></td><td class="s"> # Normal constant name</td></tr>
<tr><td class="h"><a name="59"></a>59</td><td></td><td></td><td></td><td></td><td class="s"> if ($name =~ /^_?[^\W_0-9]\w*$str_end/ and !$forbidden{$name}) {<div class="calls"><div class="calls_out"> # spent 186µs making 86 calls to <a href="constant-pm-block.html#constant__CORE_match">constant::CORE:match</a>, avg 2µs/call
# spent 67µs making 86 calls to <a href="constant-pm-block.html#constant__CORE_regcomp">constant::CORE:regcomp</a>, avg 781ns/call</div></div></td></tr>
<tr><td class="h"><a name="60"></a>60</td><td></td><td></td><td></td><td></td><td class="s"> # Everything is okay</td></tr>
<tr><td class="h"><a name="61"></a>61</td><td></td><td></td><td></td><td></td><td class="s"></td></tr>
<tr><td class="h"><a name="62"></a>62</td><td></td><td></td><td></td><td></td><td class="s"> # Name forced into main, but we're not in main. Fatal.</td></tr>
<tr><td class="h"><a name="63"></a>63</td><td></td><td></td><td></td><td></td><td class="s"> } elsif ($forced_into_main{$name} and $pkg ne 'main') {</td></tr>
<tr><td class="h"><a name="64"></a>64</td><td></td><td></td><td></td><td></td><td class="s"> require Carp;</td></tr>
<tr><td class="h"><a name="65"></a>65</td><td></td><td></td><td></td><td></td><td class="s"> Carp::croak("Constant name '$name' is forced into main::");</td></tr>
<tr><td class="h"><a name="66"></a>66</td><td></td><td></td><td></td><td></td><td class="s"></td></tr>
<tr><td class="h"><a name="67"></a>67</td><td></td><td></td><td></td><td></td><td class="s"> # Starts with double underscore. Fatal.</td></tr>
<tr><td class="h"><a name="68"></a>68</td><td></td><td></td><td></td><td></td><td class="s"> } elsif ($name =~ /^__/) {</td></tr>
<tr><td class="h"><a name="69"></a>69</td><td></td><td></td><td></td><td></td><td class="s"> require Carp;</td></tr>
<tr><td class="h"><a name="70"></a>70</td><td></td><td></td><td></td><td></td><td class="s"> Carp::croak("Constant name '$name' begins with '__'");</td></tr>
<tr><td class="h"><a name="71"></a>71</td><td></td><td></td><td></td><td></td><td class="s"></td></tr>
<tr><td class="h"><a name="72"></a>72</td><td></td><td></td><td></td><td></td><td class="s"> # Maybe the name is tolerable</td></tr>
<tr><td class="h"><a name="73"></a>73</td><td></td><td></td><td></td><td></td><td class="s"> } elsif ($name =~ /^[A-Za-z_]\w*$str_end/) {</td></tr>
<tr><td class="h"><a name="74"></a>74</td><td></td><td></td><td></td><td></td><td class="s"> # Then we'll warn only if you've asked for warnings</td></tr>
<tr><td class="h"><a name="75"></a>75</td><td></td><td></td><td></td><td></td><td class="s"> if (warnings::enabled()) {</td></tr>
<tr><td class="h"><a name="76"></a>76</td><td></td><td></td><td></td><td></td><td class="s"> if ($keywords{$name}) {</td></tr>
<tr><td class="h"><a name="77"></a>77</td><td></td><td></td><td></td><td></td><td class="s"> warnings::warn("Constant name '$name' is a Perl keyword");</td></tr>
<tr><td class="h"><a name="78"></a>78</td><td></td><td></td><td></td><td></td><td class="s"> } elsif ($forced_into_main{$name}) {</td></tr>
<tr><td class="h"><a name="79"></a>79</td><td></td><td></td><td></td><td></td><td class="s"> warnings::warn("Constant name '$name' is " .</td></tr>
<tr><td class="h"><a name="80"></a>80</td><td></td><td></td><td></td><td></td><td class="s"> "forced into package main::");</td></tr>
<tr><td class="h"><a name="81"></a>81</td><td></td><td></td><td></td><td></td><td class="s"> }</td></tr>
<tr><td class="h"><a name="82"></a>82</td><td></td><td></td><td></td><td></td><td class="s"> }</td></tr>
<tr><td class="h"><a name="83"></a>83</td><td></td><td></td><td></td><td></td><td class="s"></td></tr>
<tr><td class="h"><a name="84"></a>84</td><td></td><td></td><td></td><td></td><td class="s"> # Looks like a boolean</td></tr>
<tr><td class="h"><a name="85"></a>85</td><td></td><td></td><td></td><td></td><td class="s"> # use constant FRED == fred;</td></tr>
<tr><td class="h"><a name="86"></a>86</td><td></td><td></td><td></td><td></td><td class="s"> } elsif ($name =~ /^[01]?$str_end/) {</td></tr>
<tr><td class="h"><a name="87"></a>87</td><td></td><td></td><td></td><td></td><td class="s"> require Carp;</td></tr>
<tr><td class="h"><a name="88"></a>88</td><td></td><td></td><td></td><td></td><td class="s"> if (@_) {</td></tr>
<tr><td class="h"><a name="89"></a>89</td><td></td><td></td><td></td><td></td><td class="s"> Carp::croak("Constant name '$name' is invalid");</td></tr>
<tr><td class="h"><a name="90"></a>90</td><td></td><td></td><td></td><td></td><td class="s"> } else {</td></tr>
<tr><td class="h"><a name="91"></a>91</td><td></td><td></td><td></td><td></td><td class="s"> Carp::croak("Constant name looks like boolean value");</td></tr>
<tr><td class="h"><a name="92"></a>92</td><td></td><td></td><td></td><td></td><td class="s"> }</td></tr>
<tr><td class="h"><a name="93"></a>93</td><td></td><td></td><td></td><td></td><td class="s"></td></tr>
<tr><td class="h"><a name="94"></a>94</td><td></td><td></td><td></td><td></td><td class="s"> } else {</td></tr>
<tr><td class="h"><a name="95"></a>95</td><td></td><td></td><td></td><td></td><td class="s"> # Must have bad characters</td></tr>
<tr><td class="h"><a name="96"></a>96</td><td></td><td></td><td></td><td></td><td class="s"> require Carp;</td></tr>
<tr><td class="h"><a name="97"></a>97</td><td></td><td></td><td></td><td></td><td class="s"> Carp::croak("Constant name '$name' has invalid characters");</td></tr>
<tr><td class="h"><a name="98"></a>98</td><td></td><td></td><td></td><td></td><td class="s"> }</td></tr>
<tr><td class="h"><a name="99"></a>99</td><td></td><td></td><td></td><td></td><td class="s"></td></tr>
<tr><td class="h"><a name="100"></a>100</td><td></td><td></td><td></td><td></td><td class="s"> {</td></tr>
<tr><td class="h"><a name="101"></a>101</td><td class="c3">3</td><td class="c0"><span title="Avg 127µs">381µs</span></td><td class="c3">2</td><td class="c3">38µs</td><td class="s"><div class="calls"><div class="calls_in"># spent 24µs (9+14) within constant::BEGIN@101 which was called
# once (9µs+14µs) by Class::MOP::Method::Generated::BEGIN@15 at <a href="constant-pm-block.html#101">line 101</a></div></div> no strict 'refs';<div class="calls"><div class="calls_out"> # spent 24µs making 1 call to <a href="constant-pm-block.html#101">constant::BEGIN@101</a>
# spent 14µs making 1 call to <a href="strict-pm-block.html#39">strict::unimport</a></div></div></td></tr>
<tr><td class="h"><a name="102"></a>102</td><td class="c0">258</td><td class="c1"><span title="Avg 959ns">247µs</span></td><td></td><td></td><td class="s"> my $full_name = "${pkg}::$name";</td></tr>
<tr><td class="h"><a name="103"></a>103</td><td></td><td></td><td></td><td></td><td class="s"> $declared{$full_name}++;</td></tr>
<tr><td class="h"><a name="104"></a>104</td><td class="c0">172</td><td class="c3"><span title="Avg 400ns">69µs</span></td><td></td><td></td><td class="s"> if ($multiple || @_ == 1) {</td></tr>
<tr><td class="h"><a name="105"></a>105</td><td></td><td></td><td></td><td></td><td class="s"> my $scalar = $multiple ? $constants->{$name} : $_[0];</td></tr>
<tr><td class="h"><a name="106"></a>106</td><td class="c0">258</td><td class="c0"><span title="Avg 2µs">591µs</span></td><td></td><td></td><td class="s"> if ($symtab && !exists $symtab->{$name}) {</td></tr>
<tr><td class="h"><a name="107"></a>107</td><td></td><td></td><td></td><td></td><td class="s"> # No typeglob yet, so we can use a reference as space-</td></tr>
<tr><td class="h"><a name="108"></a>108</td><td></td><td></td><td></td><td></td><td class="s"> # efficient proxy for a constant subroutine</td></tr>
<tr><td class="h"><a name="109"></a>109</td><td></td><td></td><td></td><td></td><td class="s"> # The check in Perl_ck_rvconst knows that inlinable</td></tr>
<tr><td class="h"><a name="110"></a>110</td><td></td><td></td><td></td><td></td><td class="s"> # constants from cv_const_sv are read only. So we have to:</td></tr>
<tr><td class="h"><a name="111"></a>111</td><td></td><td></td><td></td><td></td><td class="s"> Internals::SvREADONLY($scalar, 1);<div class="calls"><div class="calls_out"> # spent 82µs making 86 calls to <a >Internals::SvREADONLY</a>, avg 958ns/call</div></div></td></tr>
<tr><td class="h"><a name="112"></a>112</td><td></td><td></td><td></td><td></td><td class="s"> $symtab->{$name} = \$scalar;</td></tr>
<tr><td class="h"><a name="113"></a>113</td><td></td><td></td><td></td><td></td><td class="s"> mro::method_changed_in($pkg);<div class="calls"><div class="calls_out"> # spent 117µs making 86 calls to <a href="mro-pm-block.html#mro__method_changed_in">mro::method_changed_in</a>, avg 1µs/call</div></div></td></tr>
<tr><td class="h"><a name="114"></a>114</td><td></td><td></td><td></td><td></td><td class="s"> } else {</td></tr>
<tr><td class="h"><a name="115"></a>115</td><td></td><td></td><td></td><td></td><td class="s"> *$full_name = sub () { $scalar };</td></tr>
<tr><td class="h"><a name="116"></a>116</td><td></td><td></td><td></td><td></td><td class="s"> }</td></tr>
<tr><td class="h"><a name="117"></a>117</td><td></td><td></td><td></td><td></td><td class="s"> } elsif (@_) {</td></tr>
<tr><td class="h"><a name="118"></a>118</td><td></td><td></td><td></td><td></td><td class="s"> my @list = @_;</td></tr>
<tr><td class="h"><a name="119"></a>119</td><td></td><td></td><td></td><td></td><td class="s"> *$full_name = sub () { @list };</td></tr>
<tr><td class="h"><a name="120"></a>120</td><td></td><td></td><td></td><td></td><td class="s"> } else {</td></tr>
<tr><td class="h"><a name="121"></a>121</td><td></td><td></td><td></td><td></td><td class="s"> *$full_name = sub () { };</td></tr>
<tr><td class="h"><a name="122"></a>122</td><td></td><td></td><td></td><td></td><td class="s"> }</td></tr>
<tr><td class="h"><a name="123"></a>123</td><td></td><td></td><td></td><td></td><td class="s"> }</td></tr>
<tr><td class="h"><a name="124"></a>124</td><td></td><td></td><td></td><td></td><td class="s"> }</td></tr>
<tr><td class="h"><a name="125"></a>125</td><td></td><td></td><td></td><td></td><td class="s">}</td></tr>
<tr><td class="h"><a name="126"></a>126</td><td></td><td></td><td></td><td></td><td class="s"></td></tr>
<tr><td class="h"><a name="127"></a>127</td><td class="c3">1</td><td class="c3"><span title="Avg 25µs">25µs</span></td><td></td><td></td><td class="s">1;</td></tr>
<tr><td class="h"><a name="128"></a>128</td><td></td><td></td><td></td><td></td><td class="s"></td></tr>
<tr><td class="h"><a name="129"></a>129</td><td></td><td></td><td></td><td></td><td class="s">__END__</td></tr>
<tr><td class="h"><a name="130"></a>130</td><td></td><td></td><td></td><td></td><td class="s"></td></tr>
<tr><td class="h"><a name="131"></a>131</td><td></td><td></td><td></td><td></td><td class="s">=head1 NAME</td></tr>
<tr><td class="h"><a name="132"></a>132</td><td></td><td></td><td></td><td></td><td class="s"></td></tr>
<tr><td class="h"><a name="133"></a>133</td><td></td><td></td><td></td><td></td><td class="s">constant - Perl pragma to declare constants</td></tr>
<tr><td class="h"><a name="134"></a>134</td><td></td><td></td><td></td><td></td><td class="s"></td></tr>
<tr><td class="h"><a name="135"></a>135</td><td></td><td></td><td></td><td></td><td class="s">=head1 SYNOPSIS</td></tr>
<tr><td class="h"><a name="136"></a>136</td><td></td><td></td><td></td><td></td><td class="s"></td></tr>
<tr><td class="h"><a name="137"></a>137</td><td></td><td></td><td></td><td></td><td class="s"> use constant PI => 4 * atan2(1, 1);</td></tr>
<tr><td class="h"><a name="138"></a>138</td><td></td><td></td><td></td><td></td><td class="s"> use constant DEBUG => 0;</td></tr>
<tr><td class="h"><a name="139"></a>139</td><td></td><td></td><td></td><td></td><td class="s"></td></tr>
<tr><td class="h"><a name="140"></a>140</td><td></td><td></td><td></td><td></td><td class="s"> print "Pi equals ", PI, "...\n" if DEBUG;</td></tr>
<tr><td class="h"><a name="141"></a>141</td><td></td><td></td><td></td><td></td><td class="s"></td></tr>
<tr><td class="h"><a name="142"></a>142</td><td></td><td></td><td></td><td></td><td class="s"> use constant {</td></tr>
<tr><td class="h"><a name="143"></a>143</td><td></td><td></td><td></td><td></td><td class="s"> SEC => 0,</td></tr>
<tr><td class="h"><a name="144"></a>144</td><td></td><td></td><td></td><td></td><td class="s"> MIN => 1,</td></tr>
<tr><td class="h"><a name="145"></a>145</td><td></td><td></td><td></td><td></td><td class="s"> HOUR => 2,</td></tr>
<tr><td class="h"><a name="146"></a>146</td><td></td><td></td><td></td><td></td><td class="s"> MDAY => 3,</td></tr>
<tr><td class="h"><a name="147"></a>147</td><td></td><td></td><td></td><td></td><td class="s"> MON => 4,</td></tr>
<tr><td class="h"><a name="148"></a>148</td><td></td><td></td><td></td><td></td><td class="s"> YEAR => 5,</td></tr>
<tr><td class="h"><a name="149"></a>149</td><td></td><td></td><td></td><td></td><td class="s"> WDAY => 6,</td></tr>
<tr><td class="h"><a name="150"></a>150</td><td></td><td></td><td></td><td></td><td class="s"> YDAY => 7,</td></tr>
<tr><td class="h"><a name="151"></a>151</td><td></td><td></td><td></td><td></td><td class="s"> ISDST => 8,</td></tr>
<tr><td class="h"><a name="152"></a>152</td><td></td><td></td><td></td><td></td><td class="s"> };</td></tr>
<tr><td class="h"><a name="153"></a>153</td><td></td><td></td><td></td><td></td><td class="s"></td></tr>
<tr><td class="h"><a name="154"></a>154</td><td></td><td></td><td></td><td></td><td class="s"> use constant WEEKDAYS => qw(</td></tr>
<tr><td class="h"><a name="155"></a>155</td><td></td><td></td><td></td><td></td><td class="s"> Sunday Monday Tuesday Wednesday Thursday Friday Saturday</td></tr>
<tr><td class="h"><a name="156"></a>156</td><td></td><td></td><td></td><td></td><td class="s"> );</td></tr>
<tr><td class="h"><a name="157"></a>157</td><td></td><td></td><td></td><td></td><td class="s"></td></tr>
<tr><td class="h"><a name="158"></a>158</td><td></td><td></td><td></td><td></td><td class="s"> print "Today is ", (WEEKDAYS)[ (localtime)[WDAY] ], ".\n";</td></tr>
<tr><td class="h"><a name="159"></a>159</td><td></td><td></td><td></td><td></td><td class="s"></td></tr>
<tr><td class="h"><a name="160"></a>160</td><td></td><td></td><td></td><td></td><td class="s">=head1 DESCRIPTION</td></tr>
<tr><td class="h"><a name="161"></a>161</td><td></td><td></td><td></td><td></td><td class="s"></td></tr>
<tr><td class="h"><a name="162"></a>162</td><td></td><td></td><td></td><td></td><td class="s">This pragma allows you to declare constants at compile-time.</td></tr>
<tr><td class="h"><a name="163"></a>163</td><td></td><td></td><td></td><td></td><td class="s"></td></tr>
<tr><td class="h"><a name="164"></a>164</td><td></td><td></td><td></td><td></td><td class="s">When you declare a constant such as C<PI> using the method shown</td></tr>
<tr><td class="h"><a name="165"></a>165</td><td></td><td></td><td></td><td></td><td class="s">above, each machine your script runs upon can have as many digits</td></tr>
<tr><td class="h"><a name="166"></a>166</td><td></td><td></td><td></td><td></td><td class="s">of accuracy as it can use. Also, your program will be easier to</td></tr>
<tr><td class="h"><a name="167"></a>167</td><td></td><td></td><td></td><td></td><td class="s">read, more likely to be maintained (and maintained correctly), and</td></tr>
<tr><td class="h"><a name="168"></a>168</td><td></td><td></td><td></td><td></td><td class="s">far less likely to send a space probe to the wrong planet because</td></tr>
<tr><td class="h"><a name="169"></a>169</td><td></td><td></td><td></td><td></td><td class="s">nobody noticed the one equation in which you wrote C<3.14195>.</td></tr>
<tr><td class="h"><a name="170"></a>170</td><td></td><td></td><td></td><td></td><td class="s"></td></tr>
<tr><td class="h"><a name="171"></a>171</td><td></td><td></td><td></td><td></td><td class="s">When a constant is used in an expression, Perl replaces it with its</td></tr>
<tr><td class="h"><a name="172"></a>172</td><td></td><td></td><td></td><td></td><td class="s">value at compile time, and may then optimize the expression further.</td></tr>
<tr><td class="h"><a name="173"></a>173</td><td></td><td></td><td></td><td></td><td class="s">In particular, any code in an C<if (CONSTANT)> block will be optimized</td></tr>
<tr><td class="h"><a name="174"></a>174</td><td></td><td></td><td></td><td></td><td class="s">away if the constant is false.</td></tr>
<tr><td class="h"><a name="175"></a>175</td><td></td><td></td><td></td><td></td><td class="s"></td></tr>
<tr><td class="h"><a name="176"></a>176</td><td></td><td></td><td></td><td></td><td class="s">=head1 NOTES</td></tr>
<tr><td class="h"><a name="177"></a>177</td><td></td><td></td><td></td><td></td><td class="s"></td></tr>
<tr><td class="h"><a name="178"></a>178</td><td></td><td></td><td></td><td></td><td class="s">As with all C<use> directives, defining a constant happens at</td></tr>
<tr><td class="h"><a name="179"></a>179</td><td></td><td></td><td></td><td></td><td class="s">compile time. Thus, it's probably not correct to put a constant</td></tr>
<tr><td class="h"><a name="180"></a>180</td><td></td><td></td><td></td><td></td><td class="s">declaration inside of a conditional statement (like C<if ($foo)</td></tr>
<tr><td class="h"><a name="181"></a>181</td><td></td><td></td><td></td><td></td><td class="s">{ use constant ... }>).</td></tr>
<tr><td class="h"><a name="182"></a>182</td><td></td><td></td><td></td><td></td><td class="s"></td></tr>
<tr><td class="h"><a name="183"></a>183</td><td></td><td></td><td></td><td></td><td class="s">Constants defined using this module cannot be interpolated into</td></tr>
<tr><td class="h"><a name="184"></a>184</td><td></td><td></td><td></td><td></td><td class="s">strings like variables. However, concatenation works just fine:</td></tr>
<tr><td class="h"><a name="185"></a>185</td><td></td><td></td><td></td><td></td><td class="s"></td></tr>
<tr><td class="h"><a name="186"></a>186</td><td></td><td></td><td></td><td></td><td class="s"> print "Pi equals PI...\n"; # WRONG: does not expand "PI"</td></tr>
<tr><td class="h"><a name="187"></a>187</td><td></td><td></td><td></td><td></td><td class="s"> print "Pi equals ".PI."...\n"; # right</td></tr>
<tr><td class="h"><a name="188"></a>188</td><td></td><td></td><td></td><td></td><td class="s"></td></tr>
<tr><td class="h"><a name="189"></a>189</td><td></td><td></td><td></td><td></td><td class="s">Even though a reference may be declared as a constant, the reference may</td></tr>
<tr><td class="h"><a name="190"></a>190</td><td></td><td></td><td></td><td></td><td class="s">point to data which may be changed, as this code shows.</td></tr>
<tr><td class="h"><a name="191"></a>191</td><td></td><td></td><td></td><td></td><td class="s"></td></tr>
<tr><td class="h"><a name="192"></a>192</td><td></td><td></td><td></td><td></td><td class="s"> use constant ARRAY => [ 1,2,3,4 ];</td></tr>
<tr><td class="h"><a name="193"></a>193</td><td></td><td></td><td></td><td></td><td class="s"> print ARRAY->[1];</td></tr>
<tr><td class="h"><a name="194"></a>194</td><td></td><td></td><td></td><td></td><td class="s"> ARRAY->[1] = " be changed";</td></tr>
<tr><td class="h"><a name="195"></a>195</td><td></td><td></td><td></td><td></td><td class="s"> print ARRAY->[1];</td></tr>
<tr><td class="h"><a name="196"></a>196</td><td></td><td></td><td></td><td></td><td class="s"></td></tr>
<tr><td class="h"><a name="197"></a>197</td><td></td><td></td><td></td><td></td><td class="s">Dereferencing constant references incorrectly (such as using an array</td></tr>
<tr><td class="h"><a name="198"></a>198</td><td></td><td></td><td></td><td></td><td class="s">subscript on a constant hash reference, or vice versa) will be trapped at</td></tr>
<tr><td class="h"><a name="199"></a>199</td><td></td><td></td><td></td><td></td><td class="s">compile time.</td></tr>
<tr><td class="h"><a name="200"></a>200</td><td></td><td></td><td></td><td></td><td class="s"></td></tr>
<tr><td class="h"><a name="201"></a>201</td><td></td><td></td><td></td><td></td><td class="s">Constants belong to the package they are defined in. To refer to a</td></tr>
<tr><td class="h"><a name="202"></a>202</td><td></td><td></td><td></td><td></td><td class="s">constant defined in another package, specify the full package name, as</td></tr>
<tr><td class="h"><a name="203"></a>203</td><td></td><td></td><td></td><td></td><td class="s">in C<Some::Package::CONSTANT>. Constants may be exported by modules,</td></tr>
<tr><td class="h"><a name="204"></a>204</td><td></td><td></td><td></td><td></td><td class="s">and may also be called as either class or instance methods, that is,</td></tr>
<tr><td class="h"><a name="205"></a>205</td><td></td><td></td><td></td><td></td><td class="s">as C<< Some::Package->CONSTANT >> or as C<< $obj->CONSTANT >> where</td></tr>
<tr><td class="h"><a name="206"></a>206</td><td></td><td></td><td></td><td></td><td class="s">C<$obj> is an instance of C<Some::Package>. Subclasses may define</td></tr>
<tr><td class="h"><a name="207"></a>207</td><td></td><td></td><td></td><td></td><td class="s">their own constants to override those in their base class.</td></tr>
<tr><td class="h"><a name="208"></a>208</td><td></td><td></td><td></td><td></td><td class="s"></td></tr>
<tr><td class="h"><a name="209"></a>209</td><td></td><td></td><td></td><td></td><td class="s">The use of all caps for constant names is merely a convention,</td></tr>
<tr><td class="h"><a name="210"></a>210</td><td></td><td></td><td></td><td></td><td class="s">although it is recommended in order to make constants stand out</td></tr>
<tr><td class="h"><a name="211"></a>211</td><td></td><td></td><td></td><td></td><td class="s">and to help avoid collisions with other barewords, keywords, and</td></tr>
<tr><td class="h"><a name="212"></a>212</td><td></td><td></td><td></td><td></td><td class="s">subroutine names. Constant names must begin with a letter or</td></tr>
<tr><td class="h"><a name="213"></a>213</td><td></td><td></td><td></td><td></td><td class="s">underscore. Names beginning with a double underscore are reserved. Some</td></tr>
<tr><td class="h"><a name="214"></a>214</td><td></td><td></td><td></td><td></td><td class="s">poor choices for names will generate warnings, if warnings are enabled at</td></tr>
<tr><td class="h"><a name="215"></a>215</td><td></td><td></td><td></td><td></td><td class="s">compile time.</td></tr>
<tr><td class="h"><a name="216"></a>216</td><td></td><td></td><td></td><td></td><td class="s"></td></tr>
<tr><td class="h"><a name="217"></a>217</td><td></td><td></td><td></td><td></td><td class="s">=head2 List constants</td></tr>
<tr><td class="h"><a name="218"></a>218</td><td></td><td></td><td></td><td></td><td class="s"></td></tr>
<tr><td class="h"><a name="219"></a>219</td><td></td><td></td><td></td><td></td><td class="s">Constants may be lists of more (or less) than one value. A constant</td></tr>
<tr><td class="h"><a name="220"></a>220</td><td></td><td></td><td></td><td></td><td class="s">with no values evaluates to C<undef> in scalar context. Note that</td></tr>
<tr><td class="h"><a name="221"></a>221</td><td></td><td></td><td></td><td></td><td class="s">constants with more than one value do I<not> return their last value in</td></tr>
<tr><td class="h"><a name="222"></a>222</td><td></td><td></td><td></td><td></td><td class="s">scalar context as one might expect. They currently return the number</td></tr>
<tr><td class="h"><a name="223"></a>223</td><td></td><td></td><td></td><td></td><td class="s">of values, but B<this may change in the future>. Do not use constants</td></tr>
<tr><td class="h"><a name="224"></a>224</td><td></td><td></td><td></td><td></td><td class="s">with multiple values in scalar context.</td></tr>
<tr><td class="h"><a name="225"></a>225</td><td></td><td></td><td></td><td></td><td class="s"></td></tr>
<tr><td class="h"><a name="226"></a>226</td><td></td><td></td><td></td><td></td><td class="s">B<NOTE:> This implies that the expression defining the value of a</td></tr>
<tr><td class="h"><a name="227"></a>227</td><td></td><td></td><td></td><td></td><td class="s">constant is evaluated in list context. This may produce surprises:</td></tr>
<tr><td class="h"><a name="228"></a>228</td><td></td><td></td><td></td><td></td><td class="s"></td></tr>
<tr><td class="h"><a name="229"></a>229</td><td></td><td></td><td></td><td></td><td class="s"> use constant TIMESTAMP => localtime; # WRONG!</td></tr>
<tr><td class="h"><a name="230"></a>230</td><td></td><td></td><td></td><td></td><td class="s"> use constant TIMESTAMP => scalar localtime; # right</td></tr>
<tr><td class="h"><a name="231"></a>231</td><td></td><td></td><td></td><td></td><td class="s"></td></tr>
<tr><td class="h"><a name="232"></a>232</td><td></td><td></td><td></td><td></td><td class="s">The first line above defines C<TIMESTAMP> as a 9-element list, as</td></tr>
<tr><td class="h"><a name="233"></a>233</td><td></td><td></td><td></td><td></td><td class="s">returned by C<localtime()> in list context. To set it to the string</td></tr>
<tr><td class="h"><a name="234"></a>234</td><td></td><td></td><td></td><td></td><td class="s">returned by C<localtime()> in scalar context, an explicit C<scalar></td></tr>
<tr><td class="h"><a name="235"></a>235</td><td></td><td></td><td></td><td></td><td class="s">keyword is required.</td></tr>
<tr><td class="h"><a name="236"></a>236</td><td></td><td></td><td></td><td></td><td class="s"></td></tr>
<tr><td class="h"><a name="237"></a>237</td><td></td><td></td><td></td><td></td><td class="s">List constants are lists, not arrays. To index or slice them, they</td></tr>
<tr><td class="h"><a name="238"></a>238</td><td></td><td></td><td></td><td></td><td class="s">must be placed in parentheses.</td></tr>
<tr><td class="h"><a name="239"></a>239</td><td></td><td></td><td></td><td></td><td class="s"></td></tr>
<tr><td class="h"><a name="240"></a>240</td><td></td><td></td><td></td><td></td><td class="s"> my @workdays = WEEKDAYS[1 .. 5]; # WRONG!</td></tr>
<tr><td class="h"><a name="241"></a>241</td><td></td><td></td><td></td><td></td><td class="s"> my @workdays = (WEEKDAYS)[1 .. 5]; # right</td></tr>
<tr><td class="h"><a name="242"></a>242</td><td></td><td></td><td></td><td></td><td class="s"></td></tr>
<tr><td class="h"><a name="243"></a>243</td><td></td><td></td><td></td><td></td><td class="s">=head2 Defining multiple constants at once</td></tr>
<tr><td class="h"><a name="244"></a>244</td><td></td><td></td><td></td><td></td><td class="s"></td></tr>
<tr><td class="h"><a name="245"></a>245</td><td></td><td></td><td></td><td></td><td class="s">Instead of writing multiple C<use constant> statements, you may define</td></tr>
<tr><td class="h"><a name="246"></a>246</td><td></td><td></td><td></td><td></td><td class="s">multiple constants in a single statement by giving, instead of the</td></tr>
<tr><td class="h"><a name="247"></a>247</td><td></td><td></td><td></td><td></td><td class="s">constant name, a reference to a hash where the keys are the names of</td></tr>
<tr><td class="h"><a name="248"></a>248</td><td></td><td></td><td></td><td></td><td class="s">the constants to be defined. Obviously, all constants defined using</td></tr>
<tr><td class="h"><a name="249"></a>249</td><td></td><td></td><td></td><td></td><td class="s">this method must have a single value.</td></tr>
<tr><td class="h"><a name="250"></a>250</td><td></td><td></td><td></td><td></td><td class="s"></td></tr>
<tr><td class="h"><a name="251"></a>251</td><td></td><td></td><td></td><td></td><td class="s"> use constant {</td></tr>
<tr><td class="h"><a name="252"></a>252</td><td></td><td></td><td></td><td></td><td class="s"> FOO => "A single value",</td></tr>
<tr><td class="h"><a name="253"></a>253</td><td></td><td></td><td></td><td></td><td class="s"> BAR => "This", "won't", "work!", # Error!</td></tr>
<tr><td class="h"><a name="254"></a>254</td><td></td><td></td><td></td><td></td><td class="s"> };</td></tr>
<tr><td class="h"><a name="255"></a>255</td><td></td><td></td><td></td><td></td><td class="s"></td></tr>
<tr><td class="h"><a name="256"></a>256</td><td></td><td></td><td></td><td></td><td class="s">This is a fundamental limitation of the way hashes are constructed in</td></tr>
<tr><td class="h"><a name="257"></a>257</td><td></td><td></td><td></td><td></td><td class="s">Perl. The error messages produced when this happens will often be</td></tr>
<tr><td class="h"><a name="258"></a>258</td><td></td><td></td><td></td><td></td><td class="s">quite cryptic -- in the worst case there may be none at all, and</td></tr>
<tr><td class="h"><a name="259"></a>259</td><td></td><td></td><td></td><td></td><td class="s">you'll only later find that something is broken.</td></tr>
<tr><td class="h"><a name="260"></a>260</td><td></td><td></td><td></td><td></td><td class="s"></td></tr>
<tr><td class="h"><a name="261"></a>261</td><td></td><td></td><td></td><td></td><td class="s">When defining multiple constants, you cannot use the values of other</td></tr>
<tr><td class="h"><a name="262"></a>262</td><td></td><td></td><td></td><td></td><td class="s">constants defined in the same declaration. This is because the</td></tr>
<tr><td class="h"><a name="263"></a>263</td><td></td><td></td><td></td><td></td><td class="s">calling package doesn't know about any constant within that group</td></tr>
<tr><td class="h"><a name="264"></a>264</td><td></td><td></td><td></td><td></td><td class="s">until I<after> the C<use> statement is finished.</td></tr>
<tr><td class="h"><a name="265"></a>265</td><td></td><td></td><td></td><td></td><td class="s"></td></tr>
<tr><td class="h"><a name="266"></a>266</td><td></td><td></td><td></td><td></td><td class="s"> use constant {</td></tr>
<tr><td class="h"><a name="267"></a>267</td><td></td><td></td><td></td><td></td><td class="s"> BITMASK => 0xAFBAEBA8,</td></tr>
<tr><td class="h"><a name="268"></a>268</td><td></td><td></td><td></td><td></td><td class="s"> NEGMASK => ~BITMASK, # Error!</td></tr>
<tr><td class="h"><a name="269"></a>269</td><td></td><td></td><td></td><td></td><td class="s"> };</td></tr>
<tr><td class="h"><a name="270"></a>270</td><td></td><td></td><td></td><td></td><td class="s"></td></tr>
<tr><td class="h"><a name="271"></a>271</td><td></td><td></td><td></td><td></td><td class="s">=head2 Magic constants</td></tr>
<tr><td class="h"><a name="272"></a>272</td><td></td><td></td><td></td><td></td><td class="s"></td></tr>
<tr><td class="h"><a name="273"></a>273</td><td></td><td></td><td></td><td></td><td class="s">Magical values and references can be made into constants at compile</td></tr>
<tr><td class="h"><a name="274"></a>274</td><td></td><td></td><td></td><td></td><td class="s">time, allowing for way cool stuff like this. (These error numbers</td></tr>
<tr><td class="h"><a name="275"></a>275</td><td></td><td></td><td></td><td></td><td class="s">aren't totally portable, alas.)</td></tr>
<tr><td class="h"><a name="276"></a>276</td><td></td><td></td><td></td><td></td><td class="s"></td></tr>
<tr><td class="h"><a name="277"></a>277</td><td></td><td></td><td></td><td></td><td class="s"> use constant E2BIG => ($! = 7);</td></tr>
<tr><td class="h"><a name="278"></a>278</td><td></td><td></td><td></td><td></td><td class="s"> print E2BIG, "\n"; # something like "Arg list too long"</td></tr>
<tr><td class="h"><a name="279"></a>279</td><td></td><td></td><td></td><td></td><td class="s"> print 0+E2BIG, "\n"; # "7"</td></tr>
<tr><td class="h"><a name="280"></a>280</td><td></td><td></td><td></td><td></td><td class="s"></td></tr>
<tr><td class="h"><a name="281"></a>281</td><td></td><td></td><td></td><td></td><td class="s">You can't produce a tied constant by giving a tied scalar as the</td></tr>
<tr><td class="h"><a name="282"></a>282</td><td></td><td></td><td></td><td></td><td class="s">value. References to tied variables, however, can be used as</td></tr>
<tr><td class="h"><a name="283"></a>283</td><td></td><td></td><td></td><td></td><td class="s">constants without any problems.</td></tr>
<tr><td class="h"><a name="284"></a>284</td><td></td><td></td><td></td><td></td><td class="s"></td></tr>
<tr><td class="h"><a name="285"></a>285</td><td></td><td></td><td></td><td></td><td class="s">=head1 TECHNICAL NOTES</td></tr>
<tr><td class="h"><a name="286"></a>286</td><td></td><td></td><td></td><td></td><td class="s"></td></tr>
<tr><td class="h"><a name="287"></a>287</td><td></td><td></td><td></td><td></td><td class="s">In the current implementation, scalar constants are actually</td></tr>
<tr><td class="h"><a name="288"></a>288</td><td></td><td></td><td></td><td></td><td class="s">inlinable subroutines. As of version 5.004 of Perl, the appropriate</td></tr>
<tr><td class="h"><a name="289"></a>289</td><td></td><td></td><td></td><td></td><td class="s">scalar constant is inserted directly in place of some subroutine</td></tr>
<tr><td class="h"><a name="290"></a>290</td><td></td><td></td><td></td><td></td><td class="s">calls, thereby saving the overhead of a subroutine call. See</td></tr>
<tr><td class="h"><a name="291"></a>291</td><td></td><td></td><td></td><td></td><td class="s">L<perlsub/"Constant Functions"> for details about how and when this</td></tr>
<tr><td class="h"><a name="292"></a>292</td><td></td><td></td><td></td><td></td><td class="s">happens.</td></tr>
<tr><td class="h"><a name="293"></a>293</td><td></td><td></td><td></td><td></td><td class="s"></td></tr>
<tr><td class="h"><a name="294"></a>294</td><td></td><td></td><td></td><td></td><td class="s">In the rare case in which you need to discover at run time whether a</td></tr>
<tr><td class="h"><a name="295"></a>295</td><td></td><td></td><td></td><td></td><td class="s">particular constant has been declared via this module, you may use</td></tr>
<tr><td class="h"><a name="296"></a>296</td><td></td><td></td><td></td><td></td><td class="s">this function to examine the hash C<%constant::declared>. If the given</td></tr>
<tr><td class="h"><a name="297"></a>297</td><td></td><td></td><td></td><td></td><td class="s">constant name does not include a package name, the current package is</td></tr>
<tr><td class="h"><a name="298"></a>298</td><td></td><td></td><td></td><td></td><td class="s">used.</td></tr>
<tr><td class="h"><a name="299"></a>299</td><td></td><td></td><td></td><td></td><td class="s"></td></tr>
<tr><td class="h"><a name="300"></a>300</td><td></td><td></td><td></td><td></td><td class="s"> sub declared ($) {</td></tr>
<tr><td class="h"><a name="301"></a>301</td><td></td><td></td><td></td><td></td><td class="s"> use constant 1.01; # don't omit this!</td></tr>
<tr><td class="h"><a name="302"></a>302</td><td></td><td></td><td></td><td></td><td class="s"> my $name = shift;</td></tr>
<tr><td class="h"><a name="303"></a>303</td><td></td><td></td><td></td><td></td><td class="s"> $name =~ s/^::/main::/;</td></tr>
<tr><td class="h"><a name="304"></a>304</td><td></td><td></td><td></td><td></td><td class="s"> my $pkg = caller;</td></tr>
<tr><td class="h"><a name="305"></a>305</td><td></td><td></td><td></td><td></td><td class="s"> my $full_name = $name =~ /::/ ? $name : "${pkg}::$name";</td></tr>
<tr><td class="h"><a name="306"></a>306</td><td></td><td></td><td></td><td></td><td class="s"> $constant::declared{$full_name};</td></tr>
<tr><td class="h"><a name="307"></a>307</td><td></td><td></td><td></td><td></td><td class="s"> }</td></tr>
<tr><td class="h"><a name="308"></a>308</td><td></td><td></td><td></td><td></td><td class="s"></td></tr>
<tr><td class="h"><a name="309"></a>309</td><td></td><td></td><td></td><td></td><td class="s">=head1 CAVEATS</td></tr>
<tr><td class="h"><a name="310"></a>310</td><td></td><td></td><td></td><td></td><td class="s"></td></tr>
<tr><td class="h"><a name="311"></a>311</td><td></td><td></td><td></td><td></td><td class="s">In the current version of Perl, list constants are not inlined</td></tr>
<tr><td class="h"><a name="312"></a>312</td><td></td><td></td><td></td><td></td><td class="s">and some symbols may be redefined without generating a warning.</td></tr>
<tr><td class="h"><a name="313"></a>313</td><td></td><td></td><td></td><td></td><td class="s"></td></tr>
<tr><td class="h"><a name="314"></a>314</td><td></td><td></td><td></td><td></td><td class="s">It is not possible to have a subroutine or a keyword with the same</td></tr>
<tr><td class="h"><a name="315"></a>315</td><td></td><td></td><td></td><td></td><td class="s">name as a constant in the same package. This is probably a Good Thing.</td></tr>
<tr><td class="h"><a name="316"></a>316</td><td></td><td></td><td></td><td></td><td class="s"></td></tr>
<tr><td class="h"><a name="317"></a>317</td><td></td><td></td><td></td><td></td><td class="s">A constant with a name in the list C<STDIN STDOUT STDERR ARGV ARGVOUT</td></tr>
<tr><td class="h"><a name="318"></a>318</td><td></td><td></td><td></td><td></td><td class="s">ENV INC SIG> is not allowed anywhere but in package C<main::>, for</td></tr>
<tr><td class="h"><a name="319"></a>319</td><td></td><td></td><td></td><td></td><td class="s">technical reasons. </td></tr>
<tr><td class="h"><a name="320"></a>320</td><td></td><td></td><td></td><td></td><td class="s"></td></tr>
<tr><td class="h"><a name="321"></a>321</td><td></td><td></td><td></td><td></td><td class="s">Unlike constants in some languages, these cannot be overridden</td></tr>
<tr><td class="h"><a name="322"></a>322</td><td></td><td></td><td></td><td></td><td class="s">on the command line or via environment variables.</td></tr>
<tr><td class="h"><a name="323"></a>323</td><td></td><td></td><td></td><td></td><td class="s"></td></tr>
<tr><td class="h"><a name="324"></a>324</td><td></td><td></td><td></td><td></td><td class="s">You can get into trouble if you use constants in a context which</td></tr>
<tr><td class="h"><a name="325"></a>325</td><td></td><td></td><td></td><td></td><td class="s">automatically quotes barewords (as is true for any subroutine call).</td></tr>
<tr><td class="h"><a name="326"></a>326</td><td></td><td></td><td></td><td></td><td class="s">For example, you can't say C<$hash{CONSTANT}> because C<CONSTANT> will</td></tr>
<tr><td class="h"><a name="327"></a>327</td><td></td><td></td><td></td><td></td><td class="s">be interpreted as a string. Use C<$hash{CONSTANT()}> or</td></tr>
<tr><td class="h"><a name="328"></a>328</td><td></td><td></td><td></td><td></td><td class="s">C<$hash{+CONSTANT}> to prevent the bareword quoting mechanism from</td></tr>
<tr><td class="h"><a name="329"></a>329</td><td></td><td></td><td></td><td></td><td class="s">kicking in. Similarly, since the C<< => >> operator quotes a bareword</td></tr>
<tr><td class="h"><a name="330"></a>330</td><td></td><td></td><td></td><td></td><td class="s">immediately to its left, you have to say C<< CONSTANT() => 'value' >></td></tr>
<tr><td class="h"><a name="331"></a>331</td><td></td><td></td><td></td><td></td><td class="s">(or simply use a comma in place of the big arrow) instead of</td></tr>
<tr><td class="h"><a name="332"></a>332</td><td></td><td></td><td></td><td></td><td class="s">C<< CONSTANT => 'value' >>.</td></tr>
<tr><td class="h"><a name="333"></a>333</td><td></td><td></td><td></td><td></td><td class="s"></td></tr>
<tr><td class="h"><a name="334"></a>334</td><td></td><td></td><td></td><td></td><td class="s">=head1 SEE ALSO</td></tr>
<tr><td class="h"><a name="335"></a>335</td><td></td><td></td><td></td><td></td><td class="s"></td></tr>
<tr><td class="h"><a name="336"></a>336</td><td></td><td></td><td></td><td></td><td class="s">L<Readonly> - Facility for creating read-only scalars, arrays, hashes.</td></tr>
<tr><td class="h"><a name="337"></a>337</td><td></td><td></td><td></td><td></td><td class="s"></td></tr>
<tr><td class="h"><a name="338"></a>338</td><td></td><td></td><td></td><td></td><td class="s">L<Const> - Facility for creating read-only variables. Similar to C<Readonly>,</td></tr>
<tr><td class="h"><a name="339"></a>339</td><td></td><td></td><td></td><td></td><td class="s">but uses C<SvREADONLY> instead of C<tie>.</td></tr>
<tr><td class="h"><a name="340"></a>340</td><td></td><td></td><td></td><td></td><td class="s"></td></tr>
<tr><td class="h"><a name="341"></a>341</td><td></td><td></td><td></td><td></td><td class="s">L<Attribute::Constant> - Make read-only variables via attribute</td></tr>
<tr><td class="h"><a name="342"></a>342</td><td></td><td></td><td></td><td></td><td class="s"></td></tr>
<tr><td class="h"><a name="343"></a>343</td><td></td><td></td><td></td><td></td><td class="s">L<Scalar::Readonly> - Perl extension to the C<SvREADONLY> scalar flag</td></tr>
<tr><td class="h"><a name="344"></a>344</td><td></td><td></td><td></td><td></td><td class="s"></td></tr>
<tr><td class="h"><a name="345"></a>345</td><td></td><td></td><td></td><td></td><td class="s">L<Hash::Util> - A selection of general-utility hash subroutines (mostly</td></tr>
<tr><td class="h"><a name="346"></a>346</td><td></td><td></td><td></td><td></td><td class="s">to lock/unlock keys and values)</td></tr>
<tr><td class="h"><a name="347"></a>347</td><td></td><td></td><td></td><td></td><td class="s"></td></tr>
<tr><td class="h"><a name="348"></a>348</td><td></td><td></td><td></td><td></td><td class="s">=head1 BUGS</td></tr>
<tr><td class="h"><a name="349"></a>349</td><td></td><td></td><td></td><td></td><td class="s"></td></tr>
<tr><td class="h"><a name="350"></a>350</td><td></td><td></td><td></td><td></td><td class="s">Please report any bugs or feature requests via the perlbug(1) utility.</td></tr>
<tr><td class="h"><a name="351"></a>351</td><td></td><td></td><td></td><td></td><td class="s"></td></tr>
<tr><td class="h"><a name="352"></a>352</td><td></td><td></td><td></td><td></td><td class="s">=head1 AUTHORS</td></tr>
<tr><td class="h"><a name="353"></a>353</td><td></td><td></td><td></td><td></td><td class="s"></td></tr>
<tr><td class="h"><a name="354"></a>354</td><td></td><td></td><td></td><td></td><td class="s">Tom Phoenix, E<lt>F<rootbeer@redcat.com>E<gt>, with help from</td></tr>
<tr><td class="h"><a name="355"></a>355</td><td></td><td></td><td></td><td></td><td class="s">many other folks.</td></tr>
<tr><td class="h"><a name="356"></a>356</td><td></td><td></td><td></td><td></td><td class="s"></td></tr>
<tr><td class="h"><a name="357"></a>357</td><td></td><td></td><td></td><td></td><td class="s">Multiple constant declarations at once added by Casey West,</td></tr>
<tr><td class="h"><a name="358"></a>358</td><td></td><td></td><td></td><td></td><td class="s">E<lt>F<casey@geeknest.com>E<gt>.</td></tr>
<tr><td class="h"><a name="359"></a>359</td><td></td><td></td><td></td><td></td><td class="s"></td></tr>
<tr><td class="h"><a name="360"></a>360</td><td></td><td></td><td></td><td></td><td class="s">Documentation mostly rewritten by Ilmari Karonen,</td></tr>
<tr><td class="h"><a name="361"></a>361</td><td></td><td></td><td></td><td></td><td class="s">E<lt>F<perl@itz.pp.sci.fi>E<gt>.</td></tr>
<tr><td class="h"><a name="362"></a>362</td><td></td><td></td><td></td><td></td><td class="s"></td></tr>
<tr><td class="h"><a name="363"></a>363</td><td></td><td></td><td></td><td></td><td class="s">This program is maintained by the Perl 5 Porters. </td></tr>
<tr><td class="h"><a name="364"></a>364</td><td></td><td></td><td></td><td></td><td class="s">The CPAN distribution is maintained by SE<eacute>bastien Aperghis-Tramoni</td></tr>
<tr><td class="h"><a name="365"></a>365</td><td></td><td></td><td></td><td></td><td class="s">E<lt>F<sebastien@aperghis.net>E<gt>.</td></tr>
<tr><td class="h"><a name="366"></a>366</td><td></td><td></td><td></td><td></td><td class="s"></td></tr>
<tr><td class="h"><a name="367"></a>367</td><td></td><td></td><td></td><td></td><td class="s">=head1 COPYRIGHT & LICENSE</td></tr>
<tr><td class="h"><a name="368"></a>368</td><td></td><td></td><td></td><td></td><td class="s"></td></tr>
<tr><td class="h"><a name="369"></a>369</td><td></td><td></td><td></td><td></td><td class="s">Copyright (C) 1997, 1999 Tom Phoenix</td></tr>
<tr><td class="h"><a name="370"></a>370</td><td></td><td></td><td></td><td></td><td class="s"></td></tr>
<tr><td class="h"><a name="371"></a>371</td><td></td><td></td><td></td><td></td><td class="s">This module is free software; you can redistribute it or modify it</td></tr>
<tr><td class="h"><a name="372"></a>372</td><td></td><td></td><td></td><td></td><td class="s">under the same terms as Perl itself.</td></tr>
<tr><td class="h"><a name="373"></a>373</td><td></td><td></td><td></td><td></td><td class="s"></td></tr>
<tr><td class="h"><a name="374"></a>374</td><td></td><td></td><td></td><td></td><td class="s">=cut</td></tr>
<tr><td class="h"><a name="constant__CORE_match"></a></td><td></td><td></td><td></td><td></td><td class="s"><div class="calls"><div class="calls_in"># spent 186µs within constant::CORE:match which was called 86 times, avg 2µs/call:
# 86 times (186µs+0s) by constant::import at <a href="constant-pm-block.html#59">line 59 of constant.pm</a>, avg 2µs/call</div></div>sub constant::CORE:match; # xsub<br /> </td></tr>
<tr><td class="h"><a name="constant__CORE_regcomp"></a></td><td></td><td></td><td></td><td></td><td class="s"><div class="calls"><div class="calls_in"># spent 67µs within constant::CORE:regcomp which was called 86 times, avg 781ns/call:
# 86 times (67µs+0s) by constant::import at <a href="constant-pm-block.html#59">line 59 of constant.pm</a>, avg 781ns/call</div></div>sub constant::CORE:regcomp; # xsub<br /> </td></tr>
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