1 =head1 How to write a perldelta
3 This is intended as a guide for how to write a perldelta. There has never
4 been a formal specification - the working rule is "fake up a document that
5 looks something close to the existing perldeltas". So if it's unclear how
6 do to do something, see if it's been done before, and if the approach works
11 Note there is a file F<Porting/perldelta_template> which contains a
12 skeleton version of a perldelta.pod file, which should normally be copied
13 in at the start of a new release.
17 Pod is more a physical markup language, rather than a logical markup language.
18 Despite that it has some built in conventions. B<Stick to them>:
22 =item * C<FE<lt>E<gt>> is for File
24 =item * C<CE<lt>E<gt>> is for Code
26 =item * C<LE<lt>E<gt>> is for Link
30 Whilst modules could also be links, usually in the context of the perldelta
31 the reference is to code C<use>ing them, rather than something within their
34 Be consistent in how bugs are referenced. One style is
40 C<RT #43010> inline, but enclose in square brackets after a sentence.
45 C<http://bugs.activestate.com/show_bug.cgi?id=72443>
57 In a list, either make every item a note, or a full sentence. Either end
58 every item with a full stop, or ensure that no item ends with one. I<regex>
59 B<xor> I<regexp> - choose exactly one, and stick to it.
63 Historically, the perldelta has consisted of a sequence of C<=head1>
64 sections, usually in the same order. Un-needed sections are deleted,
65 and if something doesn't fit nicely into the existing sections, a new
66 more appropriate section is created.
74 perl5104delta - what is new for perl v5.10.4
78 For a release on a stable branch, follows this formula:
80 This document describes differences between the 5.10.3 release and
83 For the start of a new stable branch, follows this formula:
85 This document describes differences between the 5.12.0 release and
88 Clearly this sets the scope of which changes are to be summarised in the rest
93 There was a I<Notice> section in L<perl589delta>, to carry an important
96 =item Incompatible Changes
98 For a release on a stable branch, this section aspires to be
100 There are no changes intentionally incompatible with 5.10.3. If any exist,
101 they are bugs and reports are welcome.
103 =item Core Enhancements
105 New core language features go here. Summarise user-visible core language
106 enhancements. Particularly prominent performance optimisations could go
107 here, but most should go in the L</Performance Enhancements> section.
109 Feature inside modules (pure-Perl and XS) go in L</Modules and Pragmata>
113 List any platforms that this version of perl compiles on, that previous
114 versions did not. These will either be enabled by new files in the F<hints/>
115 directories, or new subdirectories and F<README> files at the top level of the
118 =item Modules and Pragmata
120 All changes to installed files in F<ext/> and F<lib/> go here, in a list
121 ordered by distribution name. Minimally it should be the module version,
122 but it's more useful to the end user to give a paragraph's summary of the
123 module's changes. In an ideal world, dual-life modules would have a
124 F<Changes> file that could be cribbed.
126 Whilst this section could be built by incrementally working through change
127 descriptions applying to files, this is prone to error. It's better to
128 collate changes to F<ext/> and F<lib/> by module, and then summarise all
129 changes to a module as a group. This can be done by partitioning directories
130 within F<ext/> and F<lib/> to a number of people.
132 B<FIXME> - this could be automated better
134 If Module::CoreList has been updated, then F<Porting/corelist-perldelta.pl>
135 will automatically print out several sections if relevent that can be
136 pasted into F<perldelta>:
138 * New Modules and Pragmata
141 * Removed Modules and Pragmata
143 Each section will have stub entries following a template like this:
147 Upgraded from version 0.01 to 0.02
149 It does not include modules listed in F<Porting/Maintainers.pl> under
150 C<_PERLLIB>, but it's a start. Where relevent, a summary of changes can be
153 A more adventurous enhancement would be to automate grabbing
154 the changelogs for dual lived modules. For each of them, grab the relevant
155 changes files from CPAN for the old and new versions, and if the old one is
156 a strict subset of the new one, splice the extra lines right into the output,
157 as a basis for summarising.
159 (And if not, experiment with using F<git> to get the relevant part of changelog
160 for the particular file in core)
162 These could also be enhanced further by using a Pod parser module to produce
163 a parse tree of F<perl${whatever}delta.pod>, and splicing in the updates
164 correctly without throwing existing entries away.
166 If you think that's nuts, take a look at what F<pod/buildtoc> already does to
167 splice into existing Makefiles on various platforms:
169 http://perl5.git.perl.org/perl.git/blob/blead:/pod/buildtoc#l498
171 Perl is this really powerful language for text manipulation. And fun to
172 play with. We need to get that message out. :-)
174 =item Utility Changes
176 Changes to installed programs such as F<perlbug> and F<xsubpp> go here. Most
177 of these are built within the directories F<utils> and F<x2p>.
179 =item New Documentation
181 Changes which create B<new> files in F<pod/> go here.
183 B<FIXME> - this could be automated, at least as far as generating a first
190 Start with a clean exploded tarball of the previous release, and a clean
191 checkout of the branch in question
195 Take the F<MANIFEST> file of each
199 Search for lines matching C<m!^pod/.*\.pod!>
207 Explode if anyone deleted documentation. [No idea what the policy on that is
212 For each file only in the newer F<MANIFEST>
218 Use F<git> to determine its Author
222 Open the pod file itself
226 Grab the description section
230 Write out a block of text starting roughly
232 L<perlfoo>, by A. U. Thor, provides @description
238 =item Changes to Existing Documentation
240 Changes which significantly change existing files in F<pod/> go here.
241 Any changes to F<pod/perldiag.pod> should go in
242 L</New or Changed Diagnostics>.
244 =item Performance Enhancements
246 Changes which enhance performance without changing behaviour go here. There
247 may well be none in a stable release.
249 =item Installation and Configuration Improvements
251 Changes to F<Configure>, F<installperl>, F<installman>, and analogous tools
254 =item Selected Bug Fixes
256 Important bug fixes in the core language are summarised here.
257 Bug fixes in files in F<ext/> and F<lib/> are best summarised in
258 L</Modules and Pragmata>.
260 =item New or Changed Diagnostics
262 New or changed warnings emitted by the core's C<C> code go here.
264 =item Changed Internals
266 Changes which affect the interface available to C<XS> code go here.
270 Changes which create B<new> files in F<t/> go here. Changes to existing files
271 in F<t/> aren't worth summarising, although the bugs that they represent
274 Autogenerate this section by running something like this:
276 # perl newtests-perldelta.pl v5.11.1 HEAD
280 Descriptions of platform agnostic bugs we know we can't fix go here. Any
281 tests that had to be C<TODO>ed for the release would be noted here, unless
282 they were specific to a particular platform (see below).
286 Add any new known deprecations here.
288 =item Platform Specific Notes
290 Any changes specific to a particular platform. VMS and Win32 are the usual
291 stars here. It's probably best to group changes under the same section layout
292 as the main perldelta.
296 If any significant core contributor has died, we've added a short obituary
299 =item Acknowledgements
301 The list of people to thank goes here.
303 You can find the list of committers and authors by:
305 % git log v5.11.1..HEAD | perl -nlwe '$seen{$1}++ if /^Author: ([^<]*)/; END { print for sort keys %seen }'
307 And how many files where changed by:
309 % git diff v5.11.1..HEAD | diffstat
313 This doesn't usually need to be changed from the previous perldelta.
317 This doesn't usually need to be changed from the previous perldelta.