Perl: Today, Tomorrow, and Christmas

Year after year, Perl continues its steady march towards greater and greater Perlishness. Ancient mistakes are slowly sloughed off and long dreamed-of features are added. If Perl is evolving, toward what? Is it just a random collection of mutations, as desperate Perl hackers struggle to remain fit enough to survive, or is there an intelligent design behind the way Perl is changing?

In this session, Ricardo Signes (rjbs), the Perl 5 project lead, will discuss the future of the Perl language, the guiding principles of its ongoing design, and the specific changes toward which the Perl 5 Porters are working. It will also describe the way Perl 5 development really happens, how that is changing, and what we might want it to become.

Transcript

1. Perl 5 Today, Tomorrow, and Christmas
2. The Perl Dev That Was
3. The Perl Dev That Was - between perl 5.10 and perl 5.12, we changed how the release cycle works
4. The Perl Dev That Was - between perl 5.10 and perl 5.12, we changed how the release cycle works - that was three years ago (!!)
5. The Perl Dev That Was - between perl 5.10 and perl 5.12, we changed how the release cycle works - that was three years ago (!!) - hopefully this is the last time we need to talk about the old ways
6. The Old Days blead maint 5.8.0 5.8.1 5.9.0 5.9.1 5.9.2 5.8.2 5.10.0
8. The Old Days
9. The Old Days - what merits a new dev release?
10. The Old Days - what merits a new dev release? - when is a new major release done?
11. The Old Days - what merits a new dev release? - when is a new major release done? - what can get backported?
12. The Old Days - what merits a new dev release? - when is a new major release done? - what can get backported? - i.e., how stable is a stable release?
13. When I say so is when!
14. When I say so is when! - not a terrible idea in theory
15. When I say so is when! - not a terrible idea in theory - but in practice, it led to very long waits for new features to be usable
16. When I say so is when! - not a terrible idea in theory - but in practice, it led to very long waits for new features to be usable - ...which led to bad designs surviving
18. - worse, the pumpking is now busy doing
19. - worse, the pumpking is now busy doing - "cherrymaint"
20. - worse, the pumpking is now busy doing - "cherrymaint" - release planning
21. - worse, the pumpking is now busy doing - "cherrymaint" - release planning - release "paperwork"
22. - worse, the pumpking is now busy doing - "cherrymaint" - release planning - release "paperwork" - cat herding (read: arguing with angries)
23. - worse, the pumpking is now busy doing - "cherrymaint" - release planning - release "paperwork" - cat herding (read: arguing with angries) - ...but is actually a hugely valuable coder
25. The Interregnum
26. The Interregnum - the 5.10 crisis
27. The Interregnum - the 5.10 crisis - the San Diego call
28. The Interregnum - the 5.10 crisis - the San Diego call - 5.11 and the release engineers corps
29. The Interregnum - the 5.10 crisis - the San Diego call - 5.11 and the release engineers corps - any idiot can do it!
30. New Blead blead 2011-06 5.15.0
31. New Blead blead 2011-06 5.15.0 2011-07 5.15.1
32. New Blead blead 2011-06 5.15.0 2011-07 5.15.1 2011-08 5.15.2
33. New Blead blead 2011-06 5.15.0 2011-07 5.15.1 2011-08 5.15.2 2011-09 5.15.3
34. New Blead blead 2011-06 5.15.0 2011-07 5.15.1 2011-08 5.15.2 2011-09 5.15.3 2012-05 5.15.9
35. New Blead blead 2011-06 5.15.0 2011-07 5.15.1 2011-08 5.15.2 2011-09 5.15.3 2012-05 5.15.9 maint 2012-06 5.16.0
36. New Blead blead 2011-06 5.15.0 2011-07 5.15.1 2011-08 5.15.2 2011-09 5.15.3 2012-05 5.15.9 maint 2012-06 5.16.0 2012-06 5.17.0
37. New Blead blead 2011-06 5.15.0 2011-07 5.15.1 2011-08 5.15.2 2011-09 5.15.3 2012-05 5.15.9 maint 2012-06 5.16.0 2012-06 5.17.0 David G. Zefram Rik Stevan Abigail Zefram Rik
38. New Maint blead maint 2012-06 5.16.0 2012-06 5.17.0 Zefram Rik
39. New Maint blead maint 2012-06 5.16.0 2012-06 5.17.0 Zefram Rik 2012-07 5.16.1 ?
40. New Maint blead maint 2012-06 5.16.0 2012-06 5.17.0 Zefram Rik 2012-07 5.16.1 ? 2012-09 5.16.2 ?
41. New Maint blead maint 2012-06 5.16.0 2012-06 5.17.0 Zefram Rik 2012-07 5.16.1 ? 2012-09 5.16.2 2013-?? 5.16.2 ? ?
42. Minimal Maint
43. - almost all dev. burden is kept in blead Minimal Maint
44. - almost all dev. burden is kept in blead - the rules about changing maint are strict Minimal Maint
45. - almost all dev. burden is kept in blead - the rules about changing maint are strict - must be critical bug fix Minimal Maint
46. - almost all dev. burden is kept in blead - the rules about changing maint are strict - must be critical bug fix - (which includes security) Minimal Maint
47. - almost all dev. burden is kept in blead - the rules about changing maint are strict - must be critical bug fix - (which includes security) - very effective! in fact, so effective that... Minimal Maint
48. Multimaint blead 2012-06 5.16.0 2012-06 5.17.0 Zefram Rik 2012-07 5.16.1 ? 2012-09 5.16.2 2013-?? 5.16.2 ? ? maint-5.16 2011-05 5.14.0 Jesse maint-5.14
50. New Cherrymaint blead maint 2012-05 5.16.0 2012-05 5.17.0 Zefram Rik 2012-07 5.16.1 ? 2012-09 5.16.2 2013-?? 5.16.2 ? ?
51. New Cherrymaint blead maint 2012-06 5.16.0 2012-06 5.17.0 Zefram Rik 2012-07 5.16.1 ? 2012-09 5.16.2 2013-?? 5.16.2 ? ?
52. Pumpking?
54. What is the Pumpking?
55. What is the Pumpking? - the patch pumpkin
56. What is the Pumpking? - the patch pumpkin - the person with the conch
57. What is the Pumpking? - the patch pumpkin - the person with the conch - the benevolent dictator for now
58. What is the Pumpking? - the patch pumpkin - the person with the conch - the benevolent dictator for now - was: the one who could do everything
59. What is the Pumpking? - the patch pumpkin - the person with the conch - the benevolent dictator for now - was: the one who could do everything - now: the one who manages
60. Jesse and Rik
61. Jesse and Rik - we get along well
62. Jesse and Rik - we get along well - we both want what is good for Perl 5
63. Jesse and Rik - we get along well - we both want what is good for Perl 5 - but we see the future very differently
66. Rik and Jesse
67. Rik and Jesse - Jesse's "5.16 and Beyond" was inspired by his hopes and dreams
68. Rik and Jesse - Jesse's "5.16 and Beyond" was inspired by his hopes and dreams - This talk is inspired by my fears and anxieties
69. The Pumpking's Job
70. The Pumpking's Job - ...is not to make sure perl gets better. - It's to make sure perl doesn't get worse.
71. Designing Perl
72. Designing Perl - So, does that mean that the pumpking is Perl's designer?
73. Designing Perl - So, does that mean that the pumpking is Perl's designer? - Only to the extent that the designs he offers are carried out.
74. Designing Perl - So, does that mean that the pumpking is Perl's designer? - Only to the extent that the designs he offers are carried out. - Saying "make it so" depends on having a crew who will make it so.
75. Designing Perl - So, does that mean that the pumpking is Perl's designer? - Only to the extent that the designs he offers are carried out. - Saying "make it so" depends on having a crew who will make it so. - Instead, he or she is the decider.
76. How a Bill Becomes a Law
77. Mailing List Judo
78. Mailing List Judo - how do you get your change applied?
79. Mailing List Judo - how do you get your change applied? - by avoiding controversy
80. Mailing List Judo - how do you get your change applied? - by avoiding controversy - ...at least on the list
81. Syntax
82. Syntax - perl programmers obsess over it
83. Syntax - perl programmers obsess over it - even when the semantics are the real problem
84. Syntax - perl programmers obsess over it - even when the semantics are the real problem - ?->
85. Syntax - perl programmers obsess over it - even when the semantics are the real problem - ?-> - letting a syntax discussion start can be fatal
86. Changing Anything
87. Changing Anything - some argue that change itself is bad
88. Changing Anything - some argue that change itself is bad - "someone might be relying on this error"
89. Other Lunacy
90. Other Lunacy - "Your patch is nice, but why don't we do fifteen other things along with it?"
91. Other Lunacy - "Your patch is nice, but why don't we do fifteen other things along with it?" - "There are serious problems with this patch, too large to fit in the margin of this email."
92. ...and in reality...
93. ...and in reality... - These observations are true.
94. ...and in reality... - These observations are true. - So the advice to "lobby in private" seems promising.
95. ...and in reality... - These observations are true. - So the advice to "lobby in private" seems promising. - Everybody wants to avoid a long p5p thread
96. ...and in reality... - These observations are true. - So the advice to "lobby in private" seems promising. - Everybody wants to avoid a long p5p thread - …because p5p can be a horrible place.
97. U+1F4A9
98. U+1F4A9 - In most cases, everything I've just said is true.
99. U+1F4A9 - In most cases, everything I've just said is true. - …and also crap.
100. U+1F4A9 - In most cases, everything I've just said is true. - …and also crap. - p5p has, in part, a culture of fear
101. U+1F4A9 - In most cases, everything I've just said is true. - …and also crap. - p5p has, in part, a culture of fear - …of endless, horrible argument
102. Improving p5p
103. Improving p5p - if discussion on p5p was not only reliably civil…
104. Improving p5p - if discussion on p5p was not only reliably civil… - …but also technically on point…
105. Improving p5p - if discussion on p5p was not only reliably civil… - …but also technically on point… - contributors would want to engage in it
106. Improving p5p
107. Improving p5p - we would still try to avoid controversy
108. Improving p5p - we would still try to avoid controversy - …but by reaching consensus, not with tricks
109. Improving p5p - we would still try to avoid controversy - …but by reaching consensus, not with tricks - so the pumpking never needs to decide!
110. The Pumpking's Job
111. The Pumpking's Job - What will I do with all that free time?
112. The Pumpking's Job - What will I do with all that free time? - I will try to improve the list's culture.
113. The Pumpking's Job - What will I do with all that free time? - I will try to improve the list's culture. - My promise:
114. The Pumpking's Job - What will I do with all that free time? - I will try to improve the list's culture. - My promise: - I will call out unreasonable arguments and, even more, unreasonable behavior.
115. The Pumpking's Job
116. The Pumpking's Job - ...is to make sure p5p culture gets better.
117. The Final Decision
118. The Final Decision - sometimes, controversy is unavoidable
119. The Final Decision - sometimes, controversy is unavoidable - there is no consensus on whether a new feature is a good idea
120. The Final Decision - sometimes, controversy is unavoidable - there is no consensus on whether a new feature is a good idea - how can Rik still avoid having to decide?
121. CPAN, not perl
122. CPAN, not perl - can the feature be implemented on CPAN?
123. CPAN, not perl - can the feature be implemented on CPAN? - if not, why not? can that be fixed?
124. CPAN, not perl - can the feature be implemented on CPAN? - if not, why not? can that be fixed? - can its semantics be simulated for testing?
125. feature
126. feature - can the feature be lexically hidden behind feature.pm?
127. feature - can the feature be lexically hidden behind feature.pm? - (remember, not every feature needs to be in a version bundle)
128. feature - can the feature be lexically hidden behind feature.pm? - (remember, not every feature needs to be in a version bundle) - use experimental
129. use experimental ‘bind_op’; my $y = “Foo bar”; my $x := $y; :=
130. use experimental ‘bind_op’; my $y = “Foo bar”; my $x := $y; := Feature “experimental_bind_op” is not supported by Perl 5.22.0
131. Strategy of Last Resort
132. Strategy of Last Resort - the change is controversial
133. Strategy of Last Resort - the change is controversial - and can't be prototyped on CPAN
134. Strategy of Last Resort - the change is controversial - and can't be prototyped on CPAN - and can or can't go into feature.pm
135. Strategy of Last Resort - the change is controversial - and can't be prototyped on CPAN - and can or can't go into feature.pm - how do we decide?
136. The Final Decision
137. The Final Decision - is the feature small and specific?
138. The Final Decision - is the feature small and specific? - is the feature generic and unsurprising?
139. The Final Decision - is the feature small and specific? - is the feature generic and unsurprising? - is the feature teachable?
140. The Final Decision - is the feature small and specific? - is the feature generic and unsurprising? - is the feature teachable? - what's the maintenance burden?
141. The Final Decision - is the feature small and specific? - is the feature generic and unsurprising? - is the feature teachable? - what's the maintenance burden? - does it feel like it makes Perl more Perlish?
142. Perlishness
143. Perlishness - I know it when I see it.
144. Perlishness - I know it when I see it. - "gets us further along our road map"
145. The Road Map
146. The Road Map - I don't make one.
147. The Road Map - I don't make one. - I don't see the point. I don't implement perl.
148. The Road Map - I don't make one. - I don't see the point. I don't implement perl. - Submitted patches are the roads
149. Pathfinding
150. Pathfinding - Backward compatibility
151. Pathfinding - Backward compatibility - POLS
152. Pathfinding - Backward compatibility - POLS - Utility
153. Pathfinding - Backward compatibility - POLS - Utility - Conceptual simplicity
154. Pathfinding - Backward compatibility - POLS - Utility - Conceptual simplicity - Readability
155. Intelligent Design
156. Intelligent Design - always the best way to build something
157. Intelligent Design - always the best way to build something - assuming sufficient intelligence
158. Intelligent Design - always the best way to build something - assuming sufficient intelligence - and omnipotence
159. Intelligent Design - always the best way to build something - assuming sufficient intelligence - and omnipotence - i.e., great if you're God
160. Evolution
161. Evolution - seems to have worked pretty well
162. Evolution - seems to have worked pretty well - except for the billions of required deaths
163. Evolution - seems to have worked pretty well - except for the billions of required deaths - and millions of years
164. Evolution - seems to have worked pretty well - except for the billions of required deaths - and millions of years - and all those extinct species
165. Evolution - seems to have worked pretty well - except for the billions of required deaths - and millions of years - and all those extinct species - and I still ended up with an appendix
166. Intelligent Evolution
167. Intelligent Evolution - mutations are designed, not random
168. Intelligent Evolution - mutations are designed, not random - then further mutated in captivity
169. Intelligent Evolution - mutations are designed, not random - then further mutated in captivity - and possibly slaughtered before reaching the wild
172. Recovering from Error
173. Oops
174. Oops - so, Rik had to decide something
175. Oops - so, Rik had to decide something - and he made the wrong choice
176. Oops - so, Rik had to decide something - and he made the wrong choice - and everybody can tell
177. Oops - so, Rik had to decide something - and he made the wrong choice - and everybody can tell - and he wants to fix it up so the new smartassign operator is not legacy
178. Experimental?
179. Experimental? - was it marked experimental?
180. Experimental? - was it marked experimental? - if so, we can just remove the thing
181. Experimental? - was it marked experimental? - if so, we can just remove the thing - ...in theory
182. Current Experiments
183. Current Experiments - fork emulation
184. Current Experiments - fork emulation - lvalue subroutines
185. Current Experiments - fork emulation - lvalue subroutines - weak references (!?)
186. Experimental?
187. Experimental? - was it marked experimental?
188. Experimental? - was it marked experimental? - if so, we can just remove the thing
189. Experimental? - was it marked experimental? - if so, we can just remove the thing - ...in theory
190. Experimental? - was it marked experimental? - if so, we can just remove the thing - ...in theory - if not, we'll do a deprecation
191. Deprecation Cycle
192. Deprecation Cycle 1. (optional) announce in 5.16 delta that we'll probably deprecate a behavior next time
193. Deprecation Cycle 1. (optional) announce in 5.16 delta that we'll probably deprecate a behavior next time 2. start issuing warnings in 5.18
194. Deprecation Cycle 1. (optional) announce in 5.16 delta that we'll probably deprecate a behavior next time 2. start issuing warnings in 5.18 3. keep issuing them in 5.20
195. Deprecation Cycle 1. (optional) announce in 5.16 delta that we'll probably deprecate a behavior next time 2. start issuing warnings in 5.18 3. keep issuing them in 5.20 4. remove the behavior in 5.22
196. The Eternal Bug
197. The Eternal Bug - some behaviors can't be detected and made fatal practically
198. The Eternal Bug - some behaviors can't be detected and made fatal practically - arybase feature: we could remove it
199. The Eternal Bug - some behaviors can't be detected and made fatal practically - arybase feature: we could remove it - The Unicode Bug...
200. The Unicode Bug
201. my $x = acquire_input; The Unicode Bug
202. my $x = acquire_input; $x .= “Á”; # <-- that’s an A-acute The Unicode Bug
203. my $x = acquire_input; $x .= “Á”; # <-- that’s an A-acute print $x =~ /á/i ? ‘match’ : ‘no match’; The Unicode Bug
204. Features in Flight
205. pluggable syntax
206. (the MOP)
207. regexp class sets
208. $str = /\A (?[a-z] - [aeiou]) \z/x regex class sets
209. casemod escapes
210. casemod escapes
211. $input = <STDIN>; casemod escapes
212. $input = <STDIN>; # ricardo casemod escapes
213. $input = <STDIN>; # ricardo # RICARDO casemod escapes
214. $input = <STDIN>; # ricardo # RICARDO # Ricardo casemod escapes
215. $input = <STDIN>; # ricardo # RICARDO # Ricardo $str = “\u\L$input”; # Ricardo casemod escapes
216. casemod escapes
217. $let = “\L\N{LATIN CAPITAL LETTER A}”; casemod escapes
218. $let = “\L\N{LATIN CAPITAL LETTER A}”; # $let is now ‘a’ casemod escapes
219. $let = “\L\N{LATIN CAPITAL LETTER A}”; # $let is now ‘a’ $let =~ /\L\N{LATIN CAPITAL LETTER A}/; casemod escapes
220. $let = “\L\N{LATIN CAPITAL LETTER A}”; # $let is now ‘a’ $let =~ /\L\N{LATIN CAPITAL LETTER A}/; # fails!! casemod escapes
221. $let = “\L\N{LATIN CAPITAL LETTER A}”; # $let is now ‘a’ $let =~ /\L\N{LATIN CAPITAL LETTER A}/; # fails!! qr<\N{LATIN CAPITAL LETTER A}> casemod escapes
222. $let = “\L\N{LATIN CAPITAL LETTER A}”; # $let is now ‘a’ $let =~ /\L\N{LATIN CAPITAL LETTER A}/; # fails!! qr<\N{LATIN CAPITAL LETTER A}> # (?^u:\N{U+41}) casemod escapes
223. $let = “\L\N{LATIN CAPITAL LETTER A}”; # $let is now ‘a’ $let =~ /\L\N{LATIN CAPITAL LETTER A}/; # fails!! qr<\N{LATIN CAPITAL LETTER A}> # (?^u:\N{U+41}) qr<\L\N{LATIN CAPITAL LETTER A}> casemod escapes
224. $let = “\L\N{LATIN CAPITAL LETTER A}”; # $let is now ‘a’ $let =~ /\L\N{LATIN CAPITAL LETTER A}/; # fails!! qr<\N{LATIN CAPITAL LETTER A}> # (?^u:\N{U+41}) qr<\L\N{LATIN CAPITAL LETTER A}> # (?^u:\n{u+41}) casemod escapes
225. ÅÂÃÄÉÃ
226. EBCDIC
227. smartmatch
228. The Future of ~~
229. The Future of ~~ - deprecate and remove?
230. The Future of ~~ - deprecate and remove? - make pluggable with simple replacement?
231. The Future of ~~ - deprecate and remove? - make pluggable with simple replacement? - leave as is with giant warning sign?
232. The Future of ~~ - deprecate and remove? - make pluggable with simple replacement? - leave as is with giant warning sign? - and then what about given/when?
233. magic flags
234. utf8 strictness
235. (??{{ ... }})
236. The Secret Roadmap
237. slim core
238. multiple cores
239. fatal implicit close()
240. fatal implicit close()
241. { fatal implicit close()
242. { use autodie; fatal implicit close()
243. { use autodie; open my $fh, ‘>’, $filename; fatal implicit close()
244. { use autodie; open my $fh, ‘>’, $filename; $fh->print( ... ); fatal implicit close()
245. { use autodie; open my $fh, ‘>’, $filename; $fh->print( ... ); } # should die if close fails! fatal implicit close()
246. better exceptions
247. my $x = try { $y / $z } catch { return $Infinity if $_->tagged(‘divbyzero’); die $_; } better exceptions
248. MOP and pluggable OO
249. chars v. bytes
250. chars v. bytes
251. my $buf = $fh->readline; chars v. bytes
252. my $buf = $fh->readline; my $str = decode_utf8($buf); chars v. bytes
253. my $buf = $fh->readline; my $str = decode_utf8($buf); STDOUT->print( $str ); chars v. bytes
254. my $buf = $fh->readline; my $str = decode_utf8($buf); STDOUT->print( $str ); # fatal or autoencode chars v. bytes
255. autoboxing
256. autoboxing
257. @array->push(@list); autoboxing
258. @array->push(@list); $arrayref->push(@list); autoboxing
259. @array->push(@list); $arrayref->push(@list); for ($x->values) { ... } autoboxing
260. Any questions?
261. Thank you!