cannot contain the characters '/' and '|'; and any '<' or '>' should be matched. =over =item * CnameE> Link to a Perl manual page (e.g., CNet::PingE>). Note that C should not contain spaces. This syntax is also occasionally used for references to UNIX man pages, as in Ccrontab(5)E>. =item * Cname/"sec"E> or Cname/secE> Link to a section in other manual page. E.g., Cperlsyn/"For Loops"E> =item * C/"sec"E> or C/secE> or C"sec"E> Link to a section in this manual page. E.g., C/"Object Methods"E> =back A section is started by the named heading or item. For example, Cperlvar/$.E> or Cperlvar/"$."E> both link to the section started by "C<=item $.>" in perlvar. And Cperlsyn/For LoopsE> or Cperlsyn/"For Loops"E> both link to the section started by "C<=head2 For Loops>" in perlsyn. To control what text is used for display, you use "Ctext|...E>", as in: =over =item * Ctext|nameE> Link this text to that manual page. E.g., CPerl Error Messages|perldiagE> =item * Ctext|name/"sec"E> or Ctext|name/secE> Link this text to that section in that manual page. E.g., CSWITCH statements|perlsyn/"Basic BLOCKs and Switch Statements"E> =item * Ctext|/"sec"E> or Ctext|/secE> or Ctext|"sec"E> Link this text to that section in this manual page. E.g., Cthe various attributes|/"Member Data"E> =back Or you can link to a web page: =over =item * Cscheme:...E> Links to an absolute URL. For example, Chttp://www.perl.org/E>. But note that there is no corresponding Ctext|scheme:...E> syntax, for various reasons. =back =item CescapeE> -- a character escape X X<< EZ<><> >> X X Very similar to HTML/XML C<&I;> "entity references": =over =item * CltE> -- a literal E (less than) =item * CgtE> -- a literal E (greater than) =item * CverbarE> -- a literal | (Itical I) =item * CsolE> = a literal / (Iidus) The above four are optional except in other formatting codes, notably C...E>, and when preceded by a capital letter. =item * ChtmlnameE> Some non-numeric HTML entity name, such as CeacuteE>, meaning the same thing as C<é> in HTML -- i.e., a lowercase e with an acute (/-shaped) accent. =item * CnumberE> The ASCII/Latin-1/Unicode character with that number. A leading "0x" means that I is hex, as in C0x201EE>. A leading "0" means that I is octal, as in C075E>. Otherwise I is interpreted as being in decimal, as in C181E>. Note that older Pod formatters might not recognize octal or hex numeric escapes, and that many formatters cannot reliably render characters above 255. (Some formatters may even have to use compromised renderings of Latin-1 characters, like rendering CeacuteE> as just a plain "e".) =back =item CfilenameE> -- used for filenames X X<< FZ<><> >> X X Typically displayed in italics. Example: "C.cshrcE>" =item CtextE> -- text contains non-breaking spaces X X<< SZ<><> >> X X This means that the words in I should not be broken across lines. Example: S$x ? $y : $zE>>. =item Ctopic nameE> -- an index entry X X<< XZ<><> >> X X This is ignored by most formatters, but some may use it for building indexes. It always renders as empty-string. Example: Cabsolutizing relative URLsE> =item CE> -- a null (zero-effect) formatting code X X<< ZZ<><> >> X X This is rarely used. It's one way to get around using an EE...E code sometimes. For example, instead of "CltE3>" (for "NE3") you could write "CEE3>" (the "ZEE" breaks up the "N" and the "E" so they can't be considered the part of a (fictitious) "NE...E" code. =for comment This was formerly explained as a "zero-width character". But it in most parser models, it parses to nothing at all, as opposed to parsing as if it were a E or E, which are REAL zero-width characters. So "width" and "character" are exactly the wrong words. =back Most of the time, you will need only a single set of angle brackets to delimit the beginning and end of formatting codes. However, sometimes you will want to put a real right angle bracket (a greater-than sign, '>') inside of a formatting code. This is particularly common when using a formatting code to provide a different font-type for a snippet of code. As with all things in Perl, there is more than one way to do it. One way is to simply escape the closing bracket using an C code: C<$a E=E $b> This will produce: "C<$a E=E $b>" A more readable, and perhaps more "plain" way is to use an alternate set of delimiters that doesn't require a single ">" to be escaped. With the Pod formatters that are standard starting with perl5.5.660, doubled angle brackets ("<<" and ">>") may be used I For example, the following will do the trick: X C<< $a <=> $b >> In fact, you can use as many repeated angle-brackets as you like so long as you have the same number of them in the opening and closing delimiters, and make sure that whitespace immediately follows the last '<' of the opening delimiter, and immediately precedes the first '>' of the closing delimiter. (The whitespace is ignored.) So the following will also work: X C<<< $a <=> $b >>> C<<<< $a <=> $b >>>> And they all mean exactly the same as this: C<$a E=E $b> As a further example, this means that if you wanted to put these bits of code in C (code) style: open(X, ">>thing.dat") || die $! $foo->bar(); you could do it like so: C<<< open(X, ">>thing.dat") || die $! >>> C<< $foo->bar(); >> which is presumably easier to read than the old way: CEthing.dat") || die $!> C<$foo-Ebar();> This is currently supported by pod2text (Pod::Text), pod2man (Pod::Man), and any other pod2xxx or Pod::Xxxx translators that use Pod::Parser 1.093 or later, or Pod::Tree 1.02 or later. =head2 The Intent X The intent is simplicity of use, not power of expression. Paragraphs look like paragraphs (block format), so that they stand out visually, and so that I could run them through C easily to reformat them (that's F7 in my version of B, or Esc Q in my version of B). I wanted the translator to always leave the C<'> and C<`> and C<"> quotes alone, in verbatim mode, so I could slurp in a working program, shift it over four spaces, and have it print out, er, verbatim. And presumably in a monospace font. The Pod format is not necessarily sufficient for writing a book. Pod is just meant to be an idiot-proof common source for nroff, HTML, TeX, and other markup languages, as used for online documentation. Translators exist for B, B, B (that's for nroff(1) and troff(1)), B, and B. Various others are available in CPAN. =head2 Embedding Pods in Perl Modules X You can embed Pod documentation in your Perl modules and scripts. Start your documentation with an empty line, a "=head1" command at the beginning, and end it with a "=cut" command and an empty line. Perl will ignore the Pod text. See any of the supplied library modules for examples. If you're going to put your Pod at the end of the file, and you're using an __END__ or __DATA__ cut mark, make sure to put an empty line there before the first Pod command. __END__ =head1 NAME Time::Local - efficiently compute time from local and GMT time Without that empty line before the "=head1", many translators wouldn't have recognized the "=head1" as starting a Pod block. =head2 Hints for Writing Pod =over =item * X X The B command is provided for checking Pod syntax for errors and warnings. For example, it checks for completely blank lines in Pod blocks and for unknown commands and formatting codes. You should still also pass your document through one or more translators and proofread the result, or print out the result and proofread that. Some of the problems found may be bugs in the translators, which you may or may not wish to work around. =item * If you're more familiar with writing in HTML than with writing in Pod, you can try your hand at writing documentation in simple HTML, and converting it to Pod with the experimental L module, (available in CPAN), and looking at the resulting code. The experimental L module in CPAN might also be useful. =item * Many older Pod translators require the lines before every Pod command and after every Pod command (including "=cut"!) to be a blank line. Having something like this: # - - - - - - - - - - - - =item $firecracker->boom() This noisily detonates the firecracker object. =cut sub boom { ... ...will make such Pod translators completely fail to see the Pod block at all. Instead, have it like this: # - - - - - - - - - - - - =item $firecracker->boom() This noisily detonates the firecracker object. =cut sub boom { ... =item * Some older Pod translators require paragraphs (including command paragraphs like "=head2 Functions") to be separated by I empty lines. If you have an apparently empty line with some spaces on it, this might not count as a separator for those translators, and that could cause odd formatting. =item * Older translators might add wording around an LEE link, so that CFoo::BarE> may become "the Foo::Bar manpage", for example. So you shouldn't write things like CfooE documentation>, if you want the translated document to read sensibly -- instead write CFoo::Bar|Foo::BarE documentation> or Cthe Foo::Bar documentation|Foo::BarE>, to control how the link comes out. =item * Going past the 70th column in a verbatim block might be ungracefully wrapped by some formatters. =back =head1 SEE ALSO 関連項目 L, L, L, L, L, L, L. =head1 AUTHOR 著者 Larry Wall, Sean M. Burke =head1 TRANSALTE TO JAPANESE 和訳山科氷魚 (YAMASHINA Hio) Origlnal distribution is perl VERSION 5.8.8. Translated at 2006-08-31. 原典: perl VERSION 5.8.8. 翻訳日: 2006-08-31.