.\" Automatically generated by Pod::Man 4.10 (Pod::Simple 3.35) .\" .\" Standard preamble: .\" ======================================================================== .de Sp \" Vertical space (when we can't use .PP) .if t .sp .5v .if n .sp .. .de Vb \" Begin verbatim text .ft CW .nf .ne \\$1 .. .de Ve \" End verbatim text .ft R .fi .. .\" Set up some character translations and predefined strings. \*(-- will .\" give an unbreakable dash, \*(PI will give pi, \*(L" will give a left .\" double quote, and \*(R" will give a right double quote. \*(C+ will .\" give a nicer C++. Capital omega is used to do unbreakable dashes and .\" therefore won't be available. \*(C` and \*(C' expand to `' in nroff, .\" nothing in troff, for use with C<>. .tr \(*W- .ds C+ C\v'-.1v'\h'-1p'\s-2+\h'-1p'+\s0\v'.1v'\h'-1p' .ie n \{\ . ds -- \(*W- . ds PI pi . if (\n(.H=4u)&(1m=24u) .ds -- \(*W\h'-12u'\(*W\h'-12u'-\" diablo 10 pitch . if (\n(.H=4u)&(1m=20u) .ds -- \(*W\h'-12u'\(*W\h'-8u'-\" diablo 12 pitch . ds L" "" . ds R" "" . ds C` "" . ds C' "" 'br\} .el\{\ . ds -- \|\(em\| . ds PI \(*p . ds L" `` . ds R" '' . ds C` . ds C' 'br\} .\" .\" Escape single quotes in literal strings from groff's Unicode transform. .ie \n(.g .ds Aq \(aq .el .ds Aq ' .\" .\" If the F register is >0, we'll generate index entries on stderr for .\" titles (.TH), headers (.SH), subsections (.SS), items (.Ip), and index .\" entries marked with X<> in POD. Of course, you'll have to process the .\" output yourself in some meaningful fashion. .\" .\" Avoid warning from groff about undefined register 'F'. .de IX .. .nr rF 0 .if \n(.g .if rF .nr rF 1 .if (\n(rF:(\n(.g==0)) \{\ . if \nF \{\ . de IX . tm Index:\\$1\t\\n%\t"\\$2" .. . if !\nF==2 \{\ . nr % 0 . nr F 2 . \} . \} .\} .rr rF .\" ======================================================================== .\" .IX Title "PERLPOD 1" .TH PERLPOD 1 "2020-07-21" "perl v5.28.1" "Perl Programmers Reference Guide" .\" For nroff, turn off justification. Always turn off hyphenation; it makes .\" way too many mistakes in technical documents. .if n .ad l .nh .SH "NAME" perlpod \- the Plain Old Documentation format .IX Xref "POD plain old documentation" .SH "DESCRIPTION" .IX Header "DESCRIPTION" Pod is a simple-to-use markup language used for writing documentation for Perl, Perl programs, and Perl modules. .PP Translators are available for converting Pod to various formats like plain text, \s-1HTML,\s0 man pages, and more. .PP Pod markup consists of three basic kinds of paragraphs: ordinary, verbatim, and command. .SS "Ordinary Paragraph" .IX Xref "POD, ordinary paragraph" .IX Subsection "Ordinary Paragraph" Most paragraphs in your documentation will be ordinary blocks of text, like this one. You can simply type in your text without any markup whatsoever, and with just a blank line before and after. When it gets formatted, it will undergo minimal formatting, like being rewrapped, probably put into a proportionally spaced font, and maybe even justified. .PP You can use formatting codes in ordinary paragraphs, for \fBbold\fR, \&\fIitalic\fR, \f(CW\*(C`code\-style\*(C'\fR, hyperlinks, and more. Such codes are explained in the "Formatting Codes" section, below. .SS "Verbatim Paragraph" .IX Xref "POD, verbatim paragraph verbatim" .IX Subsection "Verbatim Paragraph" Verbatim paragraphs are usually used for presenting a codeblock or other text which does not require any special parsing or formatting, and which shouldn't be wrapped. .PP A verbatim paragraph is distinguished by having its first character be a space or a tab. (And commonly, all its lines begin with spaces and/or tabs.) It should be reproduced exactly, with tabs assumed to be on 8\-column boundaries. There are no special formatting codes, so you can't italicize or anything like that. A \e means \e, and nothing else. .SS "Command Paragraph" .IX Xref "POD, command" .IX Subsection "Command Paragraph" A command paragraph is used for special treatment of whole chunks of text, usually as headings or parts of lists. .PP All command paragraphs (which are typically only one line long) start with \*(L"=\*(R", followed by an identifier, followed by arbitrary text that the command can use however it pleases. Currently recognized commands are .PP .Vb 10 \& =pod \& =head1 Heading Text \& =head2 Heading Text \& =head3 Heading Text \& =head4 Heading Text \& =over indentlevel \& =item stuff \& =back \& =begin format \& =end format \& =for format text... \& =encoding type \& =cut .Ve .PP To explain them each in detail: .ie n .IP """=head1 \fIHeading Text\fP""" 4 .el .IP "\f(CW=head1 \f(CIHeading Text\f(CW\fR" 4 .IX Xref "=head1 =head2 =head3 =head4 head1 head2 head3 head4" .IX Item "=head1 Heading Text" .PD 0 .ie n .IP """=head2 \fIHeading Text\fP""" 4 .el .IP "\f(CW=head2 \f(CIHeading Text\f(CW\fR" 4 .IX Item "=head2 Heading Text" .ie n .IP """=head3 \fIHeading Text\fP""" 4 .el .IP "\f(CW=head3 \f(CIHeading Text\f(CW\fR" 4 .IX Item "=head3 Heading Text" .ie n .IP """=head4 \fIHeading Text\fP""" 4 .el .IP "\f(CW=head4 \f(CIHeading Text\f(CW\fR" 4 .IX Item "=head4 Heading Text" .PD Head1 through head4 produce headings, head1 being the highest level. The text in the rest of this paragraph is the content of the heading. For example: .Sp .Vb 1 \& =head2 Object Attributes .Ve .Sp The text \*(L"Object Attributes\*(R" comprises the heading there. The text in these heading commands can use formatting codes, as seen here: .Sp .Vb 1 \& =head2 Possible Values for C<$/> .Ve .Sp Such commands are explained in the "Formatting Codes" section, below. .ie n .IP """=over \fIindentlevel\fP""" 4 .el .IP "\f(CW=over \f(CIindentlevel\f(CW\fR" 4 .IX Xref "=over =item =back over item back" .IX Item "=over indentlevel" .PD 0 .ie n .IP """=item \fIstuff...\fP""" 4 .el .IP "\f(CW=item \f(CIstuff...\f(CW\fR" 4 .IX Item "=item stuff..." .ie n .IP """=back""" 4 .el .IP "\f(CW=back\fR" 4 .IX Item "=back" .PD Item, over, and back require a little more explanation: \*(L"=over\*(R" starts a region specifically for the generation of a list using \*(L"=item\*(R" commands, or for indenting (groups of) normal paragraphs. At the end of your list, use \*(L"=back\*(R" to end it. The \fIindentlevel\fR option to \&\*(L"=over\*(R" indicates how far over to indent, generally in ems (where one em is the width of an \*(L"M\*(R" in the document's base font) or roughly comparable units; if there is no \fIindentlevel\fR option, it defaults to four. (And some formatters may just ignore whatever \fIindentlevel\fR you provide.) In the \fIstuff\fR in \f(CW\*(C`=item \f(CIstuff...\f(CW\*(C'\fR, you may use formatting codes, as seen here: .Sp .Vb 1 \& =item Using C<$|> to Control Buffering .Ve .Sp Such commands are explained in the "Formatting Codes" section, below. .Sp Note also that there are some basic rules to using \*(L"=over\*(R" ... \&\*(L"=back\*(R" regions: .RS 4 .IP "\(bu" 4 Don't use \*(L"=item\*(R"s outside of an \*(L"=over\*(R" ... \*(L"=back\*(R" region. .IP "\(bu" 4 The first thing after the \*(L"=over\*(R" command should be an \*(L"=item\*(R", unless there aren't going to be any items at all in this \*(L"=over\*(R" ... \*(L"=back\*(R" region. .IP "\(bu" 4 Don't put "=head\fIn\fR\*(L" commands inside an \*(R"=over\*(L" ... \*(R"=back" region. .IP "\(bu" 4 And perhaps most importantly, keep the items consistent: either use \&\*(L"=item *\*(R" for all of them, to produce bullets; or use \*(L"=item 1.\*(R", \&\*(L"=item 2.\*(R", etc., to produce numbered lists; or use \*(L"=item foo\*(R", \&\*(L"=item bar\*(R", etc.\-\-namely, things that look nothing like bullets or numbers. .Sp If you start with bullets or numbers, stick with them, as formatters use the first \*(L"=item\*(R" type to decide how to format the list. .RE .RS 4 .RE .ie n .IP """=cut""" 4 .el .IP "\f(CW=cut\fR" 4 .IX Xref "=cut cut" .IX Item "=cut" To end a Pod block, use a blank line, then a line beginning with \*(L"=cut\*(R", and a blank line after it. This lets Perl (and the Pod formatter) know that this is where Perl code is resuming. (The blank line before the \*(L"=cut\*(R" is not technically necessary, but many older Pod processors require it.) .ie n .IP """=pod""" 4 .el .IP "\f(CW=pod\fR" 4 .IX Xref "=pod pod" .IX Item "=pod" The \*(L"=pod\*(R" command by itself doesn't do much of anything, but it signals to Perl (and Pod formatters) that a Pod block starts here. A Pod block starts with \fIany\fR command paragraph, so a \*(L"=pod\*(R" command is usually used just when you want to start a Pod block with an ordinary paragraph or a verbatim paragraph. For example: .Sp .Vb 1 \& =item stuff() \& \& This function does stuff. \& \& =cut \& \& sub stuff { \& ... \& } \& \& =pod \& \& Remember to check its return value, as in: \& \& stuff() || die "Couldn\*(Aqt do stuff!"; \& \& =cut .Ve .ie n .IP """=begin \fIformatname\fP""" 4 .el .IP "\f(CW=begin \f(CIformatname\f(CW\fR" 4 .IX Xref "=begin =end =for begin end for" .IX Item "=begin formatname" .PD 0 .ie n .IP """=end \fIformatname\fP""" 4 .el .IP "\f(CW=end \f(CIformatname\f(CW\fR" 4 .IX Item "=end formatname" .ie n .IP """=for \fIformatname\fP \fItext...\fP""" 4 .el .IP "\f(CW=for \f(CIformatname\f(CW \f(CItext...\f(CW\fR" 4 .IX Item "=for formatname text..." .PD For, begin, and end will let you have regions of text/code/data that are not generally interpreted as normal Pod text, but are passed directly to particular formatters, or are otherwise special. A formatter that can use that format will use the region, otherwise it will be completely ignored. .Sp A command "=begin \fIformatname\fR\*(L", some paragraphs, and a command \*(R"=end \fIformatname\fR", mean that the text/data in between is meant for formatters that understand the special format called \fIformatname\fR. For example, .Sp .Vb 1 \& =begin html \& \&
\&

This is a raw HTML paragraph

\& \& =end html .Ve .Sp The command "=for \fIformatname\fR \fItext...\fR" specifies that the remainder of just this paragraph (starting right after \fIformatname\fR) is in that special format. .Sp .Vb 2 \& =for html
\&

This is a raw HTML paragraph

.Ve .Sp This means the same thing as the above \*(L"=begin html\*(R" ... \*(L"=end html\*(R" region. .Sp That is, with \*(L"=for\*(R", you can have only one paragraph's worth of text (i.e., the text in \*(L"=foo targetname text...\*(R"), but with \&\*(L"=begin targetname\*(R" ... \*(L"=end targetname\*(R", you can have any amount of stuff in between. (Note that there still must be a blank line after the \*(L"=begin\*(R" command and a blank line before the \*(L"=end\*(R" command.) .Sp Here are some examples of how to use these: .Sp .Vb 1 \& =begin html \& \&
Figure 1.

\& \& =end html \& \& =begin text \& \& \-\-\-\-\-\-\-\-\-\-\-\-\-\-\- \& | foo | \& | bar | \& \-\-\-\-\-\-\-\-\-\-\-\-\-\-\- \& \& ^^^^ Figure 1. ^^^^ \& \& =end text .Ve .Sp Some format names that formatters currently are known to accept include \*(L"roff\*(R", \*(L"man\*(R", \*(L"latex\*(R", \*(L"tex\*(R", \*(L"text\*(R", and \*(L"html\*(R". (Some formatters will treat some of these as synonyms.) .Sp A format name of \*(L"comment\*(R" is common for just making notes (presumably to yourself) that won't appear in any formatted version of the Pod document: .Sp .Vb 2 \& =for comment \& Make sure that all the available options are documented! .Ve .Sp Some \fIformatnames\fR will require a leading colon (as in \&\f(CW"=for :formatname"\fR, or \&\f(CW"=begin :formatname" ... "=end :formatname"\fR), to signal that the text is not raw data, but instead \fIis\fR Pod text (i.e., possibly containing formatting codes) that's just not for normal formatting (e.g., may not be a normal-use paragraph, but might be for formatting as a footnote). .ie n .IP """=encoding \fIencodingname\fP""" 4 .el .IP "\f(CW=encoding \f(CIencodingname\f(CW\fR" 4 .IX Xref "=encoding encoding" .IX Item "=encoding encodingname" This command is used for declaring the encoding of a document. Most users won't need this; but if your encoding isn't US-ASCII, then put a \f(CW\*(C`=encoding \f(CIencodingname\f(CW\*(C'\fR command very early in the document so that pod formatters will know how to decode the document. For \&\fIencodingname\fR, use a name recognized by the Encode::Supported module. Some pod formatters may try to guess between a Latin\-1 or \&\s-1CP\-1252\s0 versus \&\s-1UTF\-8\s0 encoding, but they may guess wrong. It's best to be explicit if you use anything besides strict \s-1ASCII.\s0 Examples: .Sp .Vb 1 \& =encoding latin1 \& \& =encoding utf8 \& \& =encoding koi8\-r \& \& =encoding ShiftJIS \& \& =encoding big5 .Ve .Sp \&\f(CW\*(C`=encoding\*(C'\fR affects the whole document, and must occur only once. .PP And don't forget, all commands but \f(CW\*(C`=encoding\*(C'\fR last up until the end of its \fIparagraph\fR, not its line. So in the examples below, you can see that every command needs the blank line after it, to end its paragraph. (And some older Pod translators may require the \f(CW\*(C`=encoding\*(C'\fR line to have a following blank line as well, even though it should be legal to omit.) .PP Some examples of lists include: .PP .Vb 1 \& =over \& \& =item * \& \& First item \& \& =item * \& \& Second item \& \& =back \& \& =over \& \& =item Foo() \& \& Description of Foo function \& \& =item Bar() \& \& Description of Bar function \& \& =back .Ve .SS "Formatting Codes" .IX Xref "POD, formatting code formatting code POD, interior sequence interior sequence" .IX Subsection "Formatting Codes" In ordinary paragraphs and in some command paragraphs, various formatting codes (a.k.a. \*(L"interior sequences\*(R") can be used: .ie n .IP """I"" \*(-- italic text" 4 .el .IP "\f(CWI\fR \*(-- italic text" 4 .IX Xref "I I<> POD, formatting code, italic italic" .IX Item "I italic text" Used for emphasis ("\f(CW\*(C`be I\*(C'\fR\*(L") and parameters (\*(R"\f(CW\*(C`redo I