1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
|
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"
"http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<title>perlpragma - perldoc.perl.org</title>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
<meta http-equiv="Content-Language" content="en-gb">
<link rel="search" type="application/opensearchdescription+xml" title="Search perldoc.perl.org" href="/static/search.xml"/>
<link href="static/css-20100830.css" rel="stylesheet" rev="stylesheet" type="text/css" media="screen">
<link href="static/exploreperl.css" rel="stylesheet" rev="stylesheet" type="text/css">
</head>
<body onLoad="perldoc.startup();" onPageShow="if (event.persisted) perldoc.startup();">
<div id="page">
<div id="header">
<div id="homepage_link">
<a href="index.html"></a>
</div>
<div id="strapline">
Perl Programming Documentation
</div>
<div id="download_link" class="download">
<a href="http://www.perl.org/get.html">Download Perl</a>
</div>
<div id="explore_link" class="download">
<a id="explore_anchor" href="#">Explore</a>
</div>
</div>
<div id="body">
<div id="left_column">
<div class="side_group">
<div class="side_panel doc_panel">
<p>Manual</p>
<ul>
<li><a href="index-overview.html">Overview</a>
<li><a href="index-tutorials.html">Tutorials</a>
<li><a href="index-faq.html">FAQs</a>
<li><a href="index-history.html">History / Changes</a>
<li><a href="index-licence.html">License</a>
</ul>
</div>
<div class="side_panel doc_panel">
<p>Reference</p>
<ul>
<li><a href="index-language.html">Language</a>
<li><a href="index-functions.html">Functions</a>
<li><a href="perlop.html">Operators</a>
<li><a href="perlvar.html">Special Variables</a>
<li><a href="index-pragmas.html">Pragmas</a>
<li><a href="index-utilities.html">Utilities</a>
<li><a href="index-internals.html">Internals</a>
<li><a href="index-platforms.html">Platform Specific</a>
</ul>
</div>
<div class="side_panel doc_panel">
<p>Modules</p>
<ul>
<li>
<a href="index-modules-A.html">A</a>
•
<a href="index-modules-B.html">B</a>
•
<a href="index-modules-C.html">C</a>
•
<a href="index-modules-D.html">D</a>
•
<a href="index-modules-E.html">E</a>
<li>
<a href="index-modules-F.html">F</a>
•
<a href="index-modules-G.html">G</a>
•
<a href="index-modules-H.html">H</a>
•
<a href="index-modules-I.html">I</a>
•
<a href="index-modules-L.html">L</a>
<li>
<a href="index-modules-M.html">M</a>
•
<a href="index-modules-N.html">N</a>
•
<a href="index-modules-O.html">O</a>
•
<a href="index-modules-P.html">P</a>
•
<a href="index-modules-S.html">S</a>
<li>
<a href="index-modules-T.html">T</a>
•
<a href="index-modules-U.html">U</a>
•
<a href="index-modules-X.html">X</a>
</ul>
</div>
<div class="side_panel doc_panel">
<p>Tools</p>
<ul>
<li><a href="preferences.html">Preferences</a>
</ul>
</div>
</div>
</div>
<div id="centre_column">
<div id="content_header">
<div id="title_bar">
<div id="page_name">
<h1>perlpragma</h1>
</div>
<div id="perl_version">
Perl 5 version 22.0 documentation
</div>
<div class="page_links" id="page_links_top">
<a href="#" onClick="toolbar.goToTop();return false;">Go to top</a>
</div>
<div class="page_links" id="page_links_bottom">
<a href="#" id="page_index_toggle">Show page index</a> •
<a href="#" id="recent_pages_toggle">Show recent pages</a>
</div>
<div id="search_form">
<form action="search.html" method="GET" id="search">
<input type="text" name="q" id="search_box" alt="Search">
</form>
</div>
</div>
<div id="breadcrumbs">
<a href="index.html">Home</a> >
<a href="index-tutorials.html">Tutorials</a> >
perlpragma
</div>
</div>
<div id="content_body">
<!--[if lt IE 7]>
<div class="noscript">
<p>
<strong>It looks like you're using Internet Explorer 6. This is a very old
browser which does not offer full support for modern websites.</strong>
</p>
<p>
Unfortunately this means that this website will not work on
your computer.
</p>
<p>
Don't miss out though! To view the site (and get a better experience from
many other websites), simply upgrade to
<a href="http://www.microsoft.com/windows/Internet-explorer/default.aspx">Internet
Explorer 8</a>
or download an alternative browser such as
<a href="http://www.mozilla.com/en-US/firefox/firefox.html">Firefox</a>,
<a href="http://www.apple.com/safari/download/">Safari</a>, or
<a href="http://www.google.co.uk/chrome">Google Chrome</a>.
</p>
<p>
All of these browsers are free. If you're using a PC at work, you may
need to contact your IT administrator.
</p>
</div>
<![endif]-->
<noscript>
<div class="noscript">
<p>
<strong>Please note: Many features of this site require JavaScript. You appear to have JavaScript disabled,
or are running a non-JavaScript capable web browser.</strong>
</p>
<p>
To get the best experience, please enable JavaScript or download a modern web browser such as <a href="http://www.microsoft.com/windows/Internet-explorer/default.aspx">Internet Explorer 8</a>, <a href="http://www.mozilla.com/en-US/firefox/firefox.html">Firefox</a>, <a href="http://www.apple.com/safari/download/">Safari</a>, or <a href="http://www.google.co.uk/chrome">Google Chrome</a>.
</p>
</div>
</noscript>
<div id="recent_pages" class="hud_container">
<div id="recent_pages_header" class="hud_header">
<div id="recent_pages_close" class="hud_close"><a href="#" onClick="recentPages.hide();return false;"></a></div>
<div id="recent_pages_title" class="hud_title"><span class="hud_span_top">Recently read</span></div>
<div id="recent_pages_topright" class="hud_topright"></div>
</div>
<div id="recent_pages_content" class="hud_content">
</div>
<div id="recent_pages_footer" class="hud_footer">
<div id="recent_pages_bottomleft" class="hud_bottomleft"></div>
<div id="recent_pages_bottom" class="hud_bottom"><span class="hud_span_bottom"></span></div>
<div id="recent_pages_resize" class="hud_resize"></div>
</div>
</div>
<div id="from_search"></div>
<h1>perlpragma</h1>
<!-- -->
<ul><li><a href="#NAME">NAME</a><li><a href="#DESCRIPTION">DESCRIPTION</a><li><a href="#A-basic-example">A basic example</a><li><a href="#Key-naming">Key naming</a><li><a href="#Implementation-details">Implementation details</a></ul><a name="NAME"></a><h1>NAME</h1>
<p>perlpragma - how to write a user pragma</p>
<a name="DESCRIPTION"></a><h1>DESCRIPTION</h1>
<p>A pragma is a module which influences some aspect of the compile time or run
time behaviour of Perl, such as <code class="inline"><span class="w">strict</span></code>
or <code class="inline"><span class="w">warnings</span></code>
. With Perl 5.10 you
are no longer limited to the built in pragmata; you can now create user
pragmata that modify the behaviour of user functions within a lexical scope.</p>
<a name="A-basic-example"></a><h1>A basic example</h1>
<p>For example, say you need to create a class implementing overloaded
mathematical operators, and would like to provide your own pragma that
functions much like <code class="inline"><a class="l_k" href="functions/use.html">use</a> <span class="w">integer</span><span class="sc">;</span></code>
You'd like this code</p>
<pre class="verbatim"><ol><li> <a class="l_k" href="functions/use.html">use</a> <span class="w">MyMaths</span><span class="sc">;</span></li><li></li><li> <a class="l_k" href="functions/my.html">my</a> <span class="i">$l</span> = <span class="w">MyMaths</span><span class="w">->new</span><span class="s">(</span><span class="n">1.2</span><span class="s">)</span><span class="sc">;</span></li><li> <a class="l_k" href="functions/my.html">my</a> <span class="i">$r</span> = <span class="w">MyMaths</span><span class="w">->new</span><span class="s">(</span><span class="n">3.4</span><span class="s">)</span><span class="sc">;</span></li><li></li><li> <a class="l_k" href="functions/print.html">print</a> <span class="q">"A: "</span><span class="cm">,</span> <span class="i">$l</span> + <span class="i">$r</span><span class="cm">,</span> <span class="q">"\n"</span><span class="sc">;</span></li><li></li><li> <a class="l_k" href="functions/use.html">use</a> <span class="w">myint</span><span class="sc">;</span></li><li> <a class="l_k" href="functions/print.html">print</a> <span class="q">"B: "</span><span class="cm">,</span> <span class="i">$l</span> + <span class="i">$r</span><span class="cm">,</span> <span class="q">"\n"</span><span class="sc">;</span></li><li></li><li> <span class="s">{</span></li><li> <a class="l_k" href="functions/no.html">no</a> <span class="w">myint</span><span class="sc">;</span></li><li> <a class="l_k" href="functions/print.html">print</a> <span class="q">"C: "</span><span class="cm">,</span> <span class="i">$l</span> + <span class="i">$r</span><span class="cm">,</span> <span class="q">"\n"</span><span class="sc">;</span></li><li> <span class="s">}</span></li><li></li><li> <a class="l_k" href="functions/print.html">print</a> <span class="q">"D: "</span><span class="cm">,</span> <span class="i">$l</span> + <span class="i">$r</span><span class="cm">,</span> <span class="q">"\n"</span><span class="sc">;</span></li><li></li><li> <a class="l_k" href="functions/no.html">no</a> <span class="w">myint</span><span class="sc">;</span></li><li> <a class="l_k" href="functions/print.html">print</a> <span class="q">"E: "</span><span class="cm">,</span> <span class="i">$l</span> + <span class="i">$r</span><span class="cm">,</span> <span class="q">"\n"</span><span class="sc">;</span></li></ol></pre><p>to give the output</p>
<pre class="verbatim"><ol><li> A: 4.6</li><li> B: 4</li><li> C: 4.6</li><li> D: 4</li><li> E: 4.6</li></ol></pre><p><i>i.e.</i>, where <code class="inline"><a class="l_k" href="functions/use.html">use</a> <span class="w">myint</span><span class="sc">;</span></code>
is in effect, addition operations are forced
to integer, whereas by default they are not, with the default behaviour being
restored via <code class="inline"><a class="l_k" href="functions/no.html">no</a> <span class="w">myint</span><span class="sc">;</span></code>
</p>
<p>The minimal implementation of the package <code class="inline"><span class="w">MyMaths</span></code>
would be something like
this:</p>
<pre class="verbatim"><ol><li><a name="package-MyMaths"></a> package <span class="i">MyMaths</span><span class="sc">;</span></li><li> <a class="l_k" href="functions/use.html">use</a> <span class="w">warnings</span><span class="sc">;</span></li><li> <a class="l_k" href="functions/use.html">use</a> <span class="w">strict</span><span class="sc">;</span></li><li> <a class="l_k" href="functions/use.html">use</a> <span class="i">myint</span><span class="s">(</span><span class="s">)</span><span class="sc">;</span></li><li> <a class="l_k" href="functions/use.html">use</a> <span class="w">overload</span> <span class="q">'+'</span> <span class="cm">=></span> <a class="l_k" href="functions/sub.html">sub</a> <span class="s">{</span></li><li> <a class="l_k" href="functions/my.html">my</a> <span class="s">(</span><span class="i">$l</span><span class="cm">,</span> <span class="i">$r</span><span class="s">)</span> = <span class="i">@_</span><span class="sc">;</span></li><li> <span class="c"># Pass 1 to check up one call level from here</span></li><li> <a class="l_k" href="functions/if.html">if</a> <span class="s">(</span><span class="i">myint::in_effect</span><span class="s">(</span><span class="n">1</span><span class="s">)</span><span class="s">)</span> <span class="s">{</span></li><li> <a class="l_k" href="functions/int.html">int</a><span class="s">(</span><span class="i">$$l</span><span class="s">)</span> + <a class="l_k" href="functions/int.html">int</a><span class="s">(</span><span class="i">$$r</span><span class="s">)</span><span class="sc">;</span></li><li> <span class="s">}</span> <a class="l_k" href="functions/else.html">else</a> <span class="s">{</span></li><li> <span class="i">$$l</span> + <span class="i">$$r</span><span class="sc">;</span></li><li> <span class="s">}</span></li><li> <span class="s">}</span><span class="sc">;</span></li><li></li><li><a name="new"></a> sub <span class="m">new</span> <span class="s">{</span></li><li> <a class="l_k" href="functions/my.html">my</a> <span class="s">(</span><span class="i">$class</span><span class="cm">,</span> <span class="i">$value</span><span class="s">)</span> = <span class="i">@_</span><span class="sc">;</span></li><li> <a class="l_k" href="functions/bless.html">bless</a> \<span class="i">$value</span><span class="cm">,</span> <span class="i">$class</span><span class="sc">;</span></li><li> <span class="s">}</span></li><li></li><li> <span class="n">1</span><span class="sc">;</span></li></ol></pre><p>Note how we load the user pragma <code class="inline"><span class="w">myint</span></code>
with an empty list <code class="inline"><span class="s">(</span><span class="s">)</span></code>
to
prevent its <code class="inline"><a class="l_k" href="functions/import.html">import</a></code> being called.</p>
<p>The interaction with the Perl compilation happens inside package <code class="inline"><span class="w">myint</span></code>
:</p>
<pre class="verbatim"><ol><li><a name="package-myint"></a> package <span class="i">myint</span><span class="sc">;</span></li><li></li><li> <a class="l_k" href="functions/use.html">use</a> <span class="w">strict</span><span class="sc">;</span></li><li> <a class="l_k" href="functions/use.html">use</a> <span class="w">warnings</span><span class="sc">;</span></li><li></li><li><a name="import"></a> sub <span class="m">import</span> <span class="s">{</span></li><li> <span class="i">$^H</span>{<span class="q">"myint/in_effect"</span>} = <span class="n">1</span><span class="sc">;</span></li><li> <span class="s">}</span></li><li></li><li><a name="unimport"></a> sub <span class="m">unimport</span> <span class="s">{</span></li><li> <span class="i">$^H</span>{<span class="q">"myint/in_effect"</span>} = <span class="n">0</span><span class="sc">;</span></li><li> <span class="s">}</span></li><li></li><li><a name="in_effect"></a> sub <span class="m">in_effect</span> <span class="s">{</span></li><li> <a class="l_k" href="functions/my.html">my</a> <span class="i">$level</span> = <a class="l_k" href="functions/shift.html">shift</a> // <span class="n">0</span><span class="sc">;</span></li><li> <a class="l_k" href="functions/my.html">my</a> <span class="i">$hinthash</span> = <span class="s">(</span><a class="l_k" href="functions/caller.html">caller</a><span class="s">(</span><span class="i">$level</span><span class="s">)</span><span class="s">)</span>[<span class="n">10</span>]<span class="sc">;</span></li><li> <a class="l_k" href="functions/return.html">return</a> <span class="i">$hinthash</span>->{<span class="q">"myint/in_effect"</span>}<span class="sc">;</span></li><li> <span class="s">}</span></li><li></li><li> <span class="n">1</span><span class="sc">;</span></li></ol></pre><p>As pragmata are implemented as modules, like any other module, <code class="inline"><a class="l_k" href="functions/use.html">use</a> <span class="w">myint</span><span class="sc">;</span></code>
becomes</p>
<pre class="verbatim"><ol><li> BEGIN <span class="s">{</span></li><li> <a class="l_k" href="functions/require.html">require</a> <span class="w">myint</span><span class="sc">;</span></li><li> <span class="w">myint</span><span class="w">->import</span><span class="s">(</span><span class="s">)</span><span class="sc">;</span></li><li> <span class="s">}</span></li></ol></pre><p>and <code class="inline"><a class="l_k" href="functions/no.html">no</a> <span class="w">myint</span><span class="sc">;</span></code>
is</p>
<pre class="verbatim"><ol><li> BEGIN <span class="s">{</span></li><li> <a class="l_k" href="functions/require.html">require</a> <span class="w">myint</span><span class="sc">;</span></li><li> <span class="w">myint</span><span class="w">->unimport</span><span class="s">(</span><span class="s">)</span><span class="sc">;</span></li><li> <span class="s">}</span></li></ol></pre><p>Hence the <code class="inline"><a class="l_k" href="functions/import.html">import</a></code> and <code class="inline"><span class="w">unimport</span></code>
routines are called at <b>compile time</b>
for the user's code.</p>
<p>User pragmata store their state by writing to the magical hash <code class="inline"><span class="i">%^H</span></code>
,
hence these two routines manipulate it. The state information in <code class="inline"><span class="i">%^H</span></code>
is
stored in the optree, and can be retrieved read-only at runtime with <code class="inline"><a class="l_k" href="functions/caller.html">caller()</a></code>,
at index 10 of the list of returned results. In the example pragma, retrieval
is encapsulated into the routine <code class="inline"><span class="i">in_effect</span><span class="s">(</span><span class="s">)</span></code>
, which takes as parameter
the number of call frames to go up to find the value of the pragma in the
user's script. This uses <code class="inline"><a class="l_k" href="functions/caller.html">caller()</a></code> to determine the value of
<code class="inline"><span class="i">$^H</span>{<span class="q">"myint/in_effect"</span>}</code>
when each line of the user's script was called, and
therefore provide the correct semantics in the subroutine implementing the
overloaded addition.</p>
<a name="Key-naming"></a><h1>Key naming</h1>
<p>There is only a single <code class="inline"><span class="i">%^H</span></code>
, but arbitrarily many modules that want
to use its scoping semantics. To avoid stepping on each other's toes,
they need to be sure to use different keys in the hash. It is therefore
conventional for a module to use only keys that begin with the module's
name (the name of its main package) and a "/" character. After this
module-identifying prefix, the rest of the key is entirely up to the
module: it may include any characters whatsoever. For example, a module
<code class="inline"><span class="w">Foo::Bar</span></code>
should use keys such as <code class="inline"><span class="w">Foo::Bar</span>/<span class="w">baz</span></code>
and <code class="inline"><span class="w">Foo::Bar</span>/<span class="i">$%</span>/<span class="w">_</span>!</code>
.
Modules following this convention all play nicely with each other.</p>
<p>The Perl core uses a handful of keys in <code class="inline"><span class="i">%^H</span></code>
which do not follow this
convention, because they predate it. Keys that follow the convention
won't conflict with the core's historical keys.</p>
<a name="Implementation-details"></a><h1>Implementation details</h1>
<p>The optree is shared between threads. This means there is a possibility that
the optree will outlive the particular thread (and therefore the interpreter
instance) that created it, so true Perl scalars cannot be stored in the
optree. Instead a compact form is used, which can only store values that are
integers (signed and unsigned), strings or <code class="inline"><a class="l_k" href="functions/undef.html">undef</a></code> - references and
floating point values are stringified. If you need to store multiple values
or complex structures, you should serialise them, for example with <code class="inline"><a class="l_k" href="functions/pack.html">pack</a></code>.
The deletion of a hash key from <code class="inline"><span class="i">%^H</span></code>
is recorded, and as ever can be
distinguished from the existence of a key with value <code class="inline"><a class="l_k" href="functions/undef.html">undef</a></code> with
<code class="inline"><a class="l_k" href="functions/exists.html">exists</a></code>.</p>
<p><b>Don't</b> attempt to store references to data structures as integers which
are retrieved via <code class="inline"><a class="l_k" href="functions/caller.html">caller</a></code> and converted back, as this will not be threadsafe.
Accesses would be to the structure without locking (which is not safe for
Perl's scalars), and either the structure has to leak, or it has to be
freed when its creating thread terminates, which may be before the optree
referencing it is deleted, if other threads outlive it.</p>
<div id="page_index" class="hud_container">
<div id="page_index_header" class="hud_header">
<div id="page_index_close" class="hud_close"><a href="#" onClick="pageIndex.hide();return false;"></a></div>
<div id="page_index_title" class="hud_title"><span class="hud_span_top">Page index</span></div>
<div id="page_index_topright" class="hud_topright"></div>
</div>
<div id="page_index_content" class="hud_content">
<ul><li><a href="#NAME">NAME</a><li><a href="#DESCRIPTION">DESCRIPTION</a><li><a href="#A-basic-example">A basic example</a><li><a href="#Key-naming">Key naming</a><li><a href="#Implementation-details">Implementation details</a></ul>
</div>
<div id="page_index_footer" class="hud_footer">
<div id="page_index_bottomleft" class="hud_bottomleft"></div>
<div id="page_index_bottom" class="hud_bottom"><span class="hud_span_bottom"></span></div>
<div id="page_index_resize" class="hud_resize"></div>
</div>
</div>
</div>
<div id="content_footer">
</div>
</div>
<div class="clear"></div>
</div>
<div id="footer">
<div id="footer_content">
<div id="footer_strapline">
perldoc.perl.org - Official documentation for the Perl programming language
</div>
<div id="footer_links">
<div id="address">
<p class="name">Contact details</p>
<p class="address">
Site maintained by <a href="mailto:jj@jonallen.info">Jon Allen (JJ)</a><br>
</p>
<p class="contact">
Documentation maintained by the <a href="http://lists.cpan.org/showlist.cgi?name=perl5-porters">Perl 5 Porters</a>
</p>
</div>
<ul class="f1">
<li>Manual
<ul class="f2">
<li><a href="index-overview.html">Overview</a>
<li><a href="index-tutorials.html">Tutorials</a>
<li><a href="index-faq.html">FAQs</a>
<li><a href="index-history.html">Changes</a>
</ul>
<li>Reference
<ul class="f2">
<li><a href="index-language.html">Language</a>
<li><a href="index-functions.html">Functions</a>
<li><a href="perlop.html">Operators</a>
<li><a href="perlvar.html">Variables</a>
</ul>
<li>Modules
<ul class="f2">
<li><a href="index-modules-A.html">Modules</a>
<li><a href="index-pragmas.html">Pragmas</a>
<li><a href="index-utilities.html">Utilities</a>
</ul>
<li>Misc
<ul class="f2">
<li><a href="index-licence.html">License</a>
<li><a href="index-internals.html">Internals</a>
<li><a href="index-platforms.html">Platforms</a>
</ul> </ul>
<div class="clear"></div>
</div>
</div>
<div id="footer_end">
</div>
</div>
</div>
<script language="JavaScript" type="text/javascript" src="static/exploreperl.js"></script>
<script language="JavaScript" src="static/combined-20100403.js" type="text/javascript"></script>
<script language="JavaScript" type="text/javascript">
perldoc.setPath(0);
perldoc.pageName = 'perlpragma';
perldoc.pageAddress = 'perlpragma.html';
perldoc.contentPage = 1;
explorePerl.render();
explorePerl.addEvents('explore_anchor');
</script>
</body>
</html>
|
