+=encoding utf8
=head1 NAME
=head1 Pod Definitions
-Pod is embedded in files, typically Perl source files -- although you
+Pod is embedded in files, typically Perl source files, although you
can write a file that's nothing but Pod.
A B<line> in a file consists of zero or more non-newline characters,
than space or tab (and terminated by a newline or end-of-file).
(I<Note:> Many older Pod parsers did not accept a line consisting of
-spaces/tabs and then a newline as a blank line -- the only lines they
+spaces/tabs and then a newline as a blank line. The only lines they
considered blank were lines consisting of I<no characters at all>,
terminated by a newline.)
is a module or program that converts Pod to some other format (HTML,
plaintext, TeX, PostScript, RTF). A B<Pod processor> might be a
formatter or translator, or might be a program that does something
-else with the Pod (like wordcounting it, scanning for index points,
+else with the Pod (like counting words, scanning for index points,
etc.).
Pod content is contained in B<Pod blocks>. A Pod block starts with a
line that matches <m/\A=[a-zA-Z]/>, and continues up to the next line
-that matches C<m/\A=cut/> -- or up to the end of the file, if there is
+that matches C<m/\A=cut/> or up to the end of the file if there is
no C<m/\A=cut/> line.
=for comment
In other words, the Pod processing handler for "head1" will apply the
same processing to "Did You Remember to CE<lt>use strict;>?" that it
-would to an ordinary paragraph -- i.e., formatting codes (like
+would to an ordinary paragraph (i.e., formatting codes like
"CE<lt>...>") are parsed and presumably formatted appropriately, and
whitespace in the form of literal spaces and/or tabs is not
significant.
whitespace character (and there's no "=begin"..."=end" region around).
The "=begin I<identifier>" ... "=end I<identifier>" commands stop
-paragraphs that they surround from being parsed as data or verbatim
+paragraphs that they surround from being parsed as ordinary or verbatim
paragraphs, if I<identifier> doesn't begin with a colon. This
is discussed in detail in the section
L</About Data Paragraphs and "=beginE<sol>=end" Regions>.
=item "=begin formatname"
+=item "=begin formatname parameter"
+
This marks the following paragraphs (until the matching "=end
formatname") as being for some special kind of processing. Unless
"formatname" begins with a colon, the contained non-command
L</About Data Paragraphs and "=beginE<sol>=end" Regions>.
It is advised that formatnames match the regexp
-C<m/\A:?[-a-zA-Z0-9_]+\z/>. Implementors should anticipate future
-expansion in the semantics and syntax of the first parameter
-to "=begin"/"=end"/"=for".
+C<m/\A:?[−a−zA−Z0−9_]+\z/>. Everything following whitespace after the
+formatname is a parameter that may be used by the formatter when dealing
+with this region. This parameter must not be repeated in the "=end"
+paragraph. Implementors should anticipate future expansion in the
+semantics and syntax of the first parameter to "=begin"/"=end"/"=for".
=item "=end formatname"
This command, which should occur early in the document (at least
before any non-US-ASCII data!), declares that this document is
encoded in the encoding I<encodingname>, which must be
-an encoding name that L<Encoding> recognizes. (Encoding's list
-of supported encodings, in L<Encoding::Supported>, is useful here.)
+an encoding name that L<Encode> recognizes. (Encode's list
+of supported encodings, in L<Encode::Supported>, is useful here.)
If the Pod parser cannot decode the declared encoding, it
should emit a warning and may abort parsing the document
altogether.
A document having more than one "=encoding" line should be
considered an error. Pod processors may silently tolerate this if
the not-first "=encoding" lines are just duplicates of the
-first one (e.g., if there's a "=use utf8" line, and later on
-another "=use utf8" line). But Pod processors should complain if
+first one (e.g., if there's a "=encoding utf8" line, and later on
+another "=encoding utf8" line). But Pod processors should complain if
there are contradictory "=encoding" lines in the same document
(e.g., if there is a "=encoding utf8" early in the document and
"=encoding big5" later). Pod processors that recognize BOMs
B<< $foo->bar(); >>
With this syntax, the whitespace character(s) after the "CE<lt><<"
-and before the ">>" (or whatever letter) are I<not> renderable -- they
+and before the ">>" (or whatever letter) are I<not> renderable. They
do not signify whitespace, are merely part of the formatting codes
themselves. That is, these are all synonymous:
and so on.
+Finally, the multiple-angle-bracket form does I<not> alter the interpretation
+of nested formatting codes, meaning that the following four example lines are
+identical in meaning:
+
+ B<example: C<$a E<lt>=E<gt> $b>>
+
+ B<example: C<< $a <=> $b >>>
+
+ B<example: C<< $a E<lt>=E<gt> $b >>>
+
+ B<<< example: C<< $a E<lt>=E<gt> $b >> >>>
+
=back
In parsing Pod, a notably tricky part is the correct parsing of
would parse as equivalent to this:
- C<$foo-E<lt>bar>
+ C<$foo-E<gt>bar>
instead of as equivalent to a "C" formatting code containing
only "$foo-", and then a "bar>" outside the "C" formatting code. This
Pod parsers should not, by default, try to coerce apostrophe (') and
quote (") into smart quotes (little 9's, 66's, 99's, etc), nor try to
turn backtick (`) into anything else but a single backtick character
-(distinct from an openquote character!), nor "--" into anything but
+(distinct from an open quote character!), nor "--" into anything but
two minus signs. They I<must never> do any of those things to text
in CE<lt>...> formatting codes, and never I<ever> to text in verbatim
paragraphs.
=item *
-It is up to individual Pod formatter to display good judgment when
+It is up to individual Pod formatter to display good judgement when
confronted with an unrenderable character (which is distinct from an
unknown EE<lt>thing> sequence that the parser couldn't resolve to
anything, renderable or not). It is good practice to map Latin letters
=item Second:
-The possibly inferred link-text -- i.e., if there was no real link
+The possibly inferred link-text; i.e., if there was no real link
text, then this is the text that we'll infer in its place. (E.g., for
"LE<lt>Getopt::Std>", the inferred link text is "Getopt::Std".)
=item Third:
The name or URL, or undef if none. (E.g., in "LE<lt>Perl
-Functions|perlfunc>", the name -- also sometimes called the page --
+Functions|perlfunc>", the name (also sometimes called the page)
is "perlfunc". In "LE<lt>/CAVEATS>", the name is undef.)
=item Fourth:
The section (AKA "item" in older perlpods), or undef if none. E.g.,
-in L<Getopt::Std/DESCRIPTION>, "DESCRIPTION" is the section. (Note
+in "LE<lt>Getopt::Std/DESCRIPTIONE<gt>", "DESCRIPTION" is the section. (Note
that this is not the same as a manpage section like the "5" in "man 5
crontab". "Section Foo" in the Pod sense means the part of the text
that's introduced by the heading or item whose text is "Foo".)
'url', # what sort of link
"http://www.perl.org/" # original content
+ L<Perl.org|http://www.perl.org/>
+ => "Perl.org", # link text
+ "http://www.perl.org/", # possibly inferred link text
+ "http://www.perl.org/", # name
+ undef, # section
+ 'url', # what sort of link
+ "Perl.org|http://www.perl.org/" # original content
+
Note that you can distinguish URL-links from anything else by the
fact that they match C<m/\A\w+:[^:\s]\S*\z/>. So
C<LE<lt>http://www.perl.comE<gt>> is a URL, but
L<B<ummE<234>stuff>|...>
For C<LE<lt>...E<gt>> codes without a "name|" part, only
-C<EE<lt>...E<gt>> and C<ZE<lt>E<gt>> codes may occur -- no
-other formatting codes. That is, authors should not use
-"C<LE<lt>BE<lt>Foo::BarE<gt>E<gt>>".
+C<EE<lt>...E<gt>> and C<ZE<lt>E<gt>> codes may occur. That is,
+authors should not use "C<LE<lt>BE<lt>Foo::BarE<gt>E<gt>>".
Note, however, that formatting codes and ZE<lt>>'s can occur in any
and all parts of an LE<lt>...> (i.e., in I<name>, I<section>, I<text>,
At time of writing, C<LE<lt>nameE<gt>> values are of two types:
either the name of a Pod page like C<LE<lt>Foo::BarE<gt>> (which
might be a real Perl module or program in an @INC / PATH
-directory, or a .pod file in those places); or the name of a UNIX
+directory, or a .pod file in those places); or the name of a Unix
man page, like C<LE<lt>crontab(5)E<gt>>. In theory, C<LE<lt>chmodE<gt>>
in ambiguous between a Pod page called "chmod", or the Unix man page
"chmod" (in whatever man-section). However, the presence of a string
in parens, as in "crontab(5)", is sufficient to signal that what
is being discussed is not a Pod page, and so is presumably a
-UNIX man page. The distinction is of no importance to many
+Unix man page. The distinction is of no importance to many
Pod processors, but some processors that render to hypertext formats
may need to distinguish them in order to know how to render a
given C<LE<lt>fooE<gt>> code.
=item *
-Previous versions of perlpod allowed for a C<LE<lt>sectionE<gt>> syntax
-(as in "C<LE<lt>Object AttributesE<gt>>"), which was not easily distinguishable
-from C<LE<lt>nameE<gt>> syntax. This syntax is no longer in the
-specification, and has been replaced by the C<LE<lt>"section"E<gt>> syntax
-(where the quotes were formerly optional). Pod parsers should tolerate
-the C<LE<lt>sectionE<gt>> syntax, for a while at least. The suggested
-heuristic for distinguishing C<LE<lt>sectionE<gt>> from C<LE<lt>nameE<gt>>
-is that if it contains any whitespace, it's a I<section>. Pod processors
-may warn about this being deprecated syntax.
+Previous versions of perlpod allowed for a C<LE<lt>sectionE<gt>> syntax (as in
+C<LE<lt>Object AttributesE<gt>>), which was not easily distinguishable from
+C<LE<lt>nameE<gt>> syntax and for C<LE<lt>"section"E<gt>> which was only
+slightly less ambiguous. This syntax is no longer in the specification, and
+has been replaced by the C<LE<lt>/sectionE<gt>> syntax (where the slash was
+formerly optional). Pod parsers should tolerate the C<LE<lt>"section"E<gt>>
+syntax, for a while at least. The suggested heuristic for distinguishing
+C<LE<lt>sectionE<gt>> from C<LE<lt>nameE<gt>> is that if it contains any
+whitespace, it's a I<section>. Pod processors should warn about this being
+deprecated syntax.
=back
Ut Enim
-But (for the forseeable future), Pod does not provide any way for Pod
+But (for the foreseeable future), Pod does not provide any way for Pod
authors to distinguish which grouping is meant by the above
"=item"-cluster structure. So formatters should format it like so:
happens that "outer" is the format name of a higher-up region.) This is
an error. Processors must by default report this as an error, and may halt
processing the document containing that error. A corollary of this is that
-regions cannot "overlap" -- i.e., the latter block above does not represent
+regions cannot "overlap". That is, the latter block above does not represent
a region called "outer" which contains X and Y, overlapping a region called
"inner" which contains Y and Z. But because it is invalid (as all
apparently overlapping regions would be), it doesn't represent that, or
https://perl5.git.perl.org / perl5.git / blobdiff