common-sense/sense.pm

=head1 NAME

common::sense - save a tree AND a kitten, use common::sense!

=head1 SYNOPSIS

 use common::sense;

 # supposed to be the same, with much lower memory usage, as:
 #
 # use utf8;
 # use strict qw(vars subs);
 # use feature qw(say state switch);
 # no warnings;
 # use warnings qw(FATAL closed threads internal debugging pack substr malloc
 #                 portable prototype inplace io pipe unpack regexp
 #                 deprecated exiting glob digit printf layer
 #                 reserved parenthesis taint closure semicolon);
 # no warnings qw(exec newline unopened);

=head1 DESCRIPTION

This module implements some sane defaults for Perl programs, as defined by
two typical (or not so typical - use your common sense) specimens of Perl
coders. In fact, after working out details on which warnings and strict
modes to enable and make fatal, we found that we (and our code written so
far, and others) fully agree on every option, even though we never used
warnings before, so it seems this module indeed reflects a "common" sense
among some long-time Perl coders.

The basic philosophy behind the choices made in common::sense can be
summarised as: "enforcing strict policies to catch as many bugs as
possible, while at the same time, not limiting the expressive power
available to the programmer".

Two typical examples of how this philosophy is applied in practise is the
handling of uninitialised and malloc warnings:

=over 4

=item I<uninitialised>

C<undef> is a well-defined feature of perl, and enabling warnings for
using it rarely catches any bugs, but considerably limits you in what you
can do, so uninitialised warnings are disabled.

=item I<malloc>

Freeing something twice on the C level is a serious bug, usually causing
memory corruption. It often leads to side effects much later in the
program and there are no advantages to not reporting this, so malloc
warnings are fatal by default.

=back

What follows is a more thorough discussion of what this module does,
and why it does it, and what the advantages (and disadvantages) of this
approach are.

=head1 RATIONALE

=over 4

=item use utf8

While it's not common sense to write your programs in UTF-8, it's quickly
becoming the most common encoding, is the designated future default
encoding for perl sources, and the most convenient encoding available
(you can do really nice quoting tricks...). Experience has shown that our
programs were either all pure ascii or utf-8, both of which will stay the
same.

There are few drawbacks to enabling UTF-8 source code by default (mainly
some speed hits due to bugs in older versions of perl), so this module
enables UTF-8 source code encoding by default.

=item use strict qw(subs vars)

Using C<use strict> is definitely common sense, but C<use strict
'refs'> definitely overshoots its usefulness. After almost two
decades of Perl hacking, we decided that it does more harm than being
useful. Specifically, constructs like these:

   @{ $var->[0] }

Must be written like this (or similarly), when C<use strict 'refs'> is in
scope, and C<$var> can legally be C<undef>:

   @{ $var->[0] || [] }

This is annoying, and doesn't shield against obvious mistakes such as
using C<"">, so one would even have to write (at least for the time
being):

   @{ defined $var->[0] ? $var->[0] : [] }

... which nobody with a bit of common sense would consider
writing: clear code is clearly something else.

Curiously enough, sometimes perl is not so strict, as this works even with
C<use strict> in scope:

   for (@{ $var->[0] }) { ...

If that isn't hypocrisy! And all that from a mere program!


=item use feature qw(say state given)

We found it annoying that we always have to enable extra features. If
something breaks because it didn't anticipate future changes, so be
it. 5.10 broke almost all our XS modules and nobody cared either (or at
least I know of nobody who really complained about gratuitous changes -
as opposed to bugs).

Few modules that are not actively maintained work with newer versions of
Perl, regardless of use feature or not, so a new major perl release means
changes to many modules - new keywords are just the tip of the iceberg.

If your code isn't alive, it's dead, Jim - be an active maintainer.

But nobody forces you to use those extra features in modules meant for
older versions of perl - common::sense of course works there as well.
There is also an important other mode where having additional features by
default is useful: commandline hacks and internal use scripts: See "much
reduced typing", below.


=item no warnings, but a lot of new errors

Ah, the dreaded warnings. Even worse, the horribly dreaded C<-w>
switch: Even though we don't care if other people use warnings (and
certainly there are useful ones), a lot of warnings simply go against the
spirit of Perl.

Most prominently, the warnings related to C<undef>. There is nothing wrong
with C<undef>: it has well-defined semantics, it is useful, and spitting
out warnings you never asked for is just evil.

The result was that every one of our modules did C<no warnings> in the
past, to avoid somebody accidentally using and forcing his bad standards
on our code. Of course, this switched off all warnings, even the useful
ones. Not a good situation. Really, the C<-w> switch should only enable
warnings for the main program only.

Funnily enough, L<perllexwarn> explicitly mentions C<-w> (and not in a
favourable way, calling it outright "wrong"), but standard utilities, such
as L<prove>, or MakeMaker when running C<make test>, still enable them
blindly.

For version 2 of common::sense, we finally sat down a few hours and went
through I<every single warning message>, identifiying - according to
common sense - all the useful ones.

This resulted in the rather impressive list in the SYNOPSIS. When we
weren't sure, we didn't include the warning, so the list might grow in
the future (we might have made a mistake, too, so the list might shrink
as well).

Note the presence of C<FATAL> in the list: we do not think that the
conditions caught by these warnings are worthy of a warning, we I<insist>
that they are worthy of I<stopping> your program, I<instantly>. They are
I<bugs>!

Therefore we consider C<common::sense> to be much stricter than C<use
warnings>, which is good if you are into strict things (we are not,
actually, but these things tend to be subjective).

After deciding on the list, we ran the module against all of our code that
uses C<common::sense> (that is almost all of our code), and found only one
occurence where one of them caused a problem: one of elmex's (unreleased)
modules contained:

   $fmt =~ s/([^\s\[]*)\[( [^\]]* )\]/\x0$1\x1$2\x0/xgo;

We quickly agreed that indeed the code should be changed, even though it
happened to do the right thing when the warning was switched off.


=item much reduced typing

Especially with version 2.0 of common::sense, the amount of boilerplate
code you need to add to gte I<this> policy is daunting. Nobody would write
this out in throwaway scripts, commandline hacks or in quick internal-use
scripts.

By using common::sense you get a defined set of policies (ours, but maybe
yours, too, if you accept them), and they are easy to apply to your
scripts: typing C<use common::sense;> is even shorter than C<use warnings;
use strict; use feature ...>.

And you can immediately use the features of your installed perl, which
is more difficult in code you release, but not usually an issue for
internal-use code (downgrades of your production perl should be rare,
right?).


=item mucho reduced memory usage

Just using all those pragmas mentioned in the SYNOPSIS together wastes
<blink>I<< B<776> kilobytes >></blink> of precious memory in my perl, for
I<every single perl process using our code>, which on our machines, is a
lot. In comparison, this module only uses I<< B<four> >> kilobytes (I even
had to write it out so it looks like more) of memory on the same platform.

The money/time/effort/electricity invested in these gigabytes (probably
petabytes globally!) of wasted memory could easily save 42 trees, and a
kitten!

Unfortunately, until everybods applies more common sense, there will still
often be modules that pull in the monster pragmas. But one can hope...

=cut

package common::sense;

our $VERSION = '3.0';

# paste this into perl to find bitmask

# no warnings;
# use warnings qw(FATAL closed threads internal debugging pack substr malloc portable prototype
#                 inplace io pipe unpack regexp deprecated exiting glob digit printf
#                 layer reserved parenthesis taint closure semicolon);
# no warnings qw(exec newline unopened);
# BEGIN { warn join "", map "\\x$_", unpack "(H2)*", ${^WARNING_BITS}; exit 0 };

# overload should be included

sub import {
   # verified with perl 5.8.0, 5.10.0
   ${^WARNING_BITS} ^= ${^WARNING_BITS} ^ "\xfc\x3f\x33\x00\x0f\xf3\xcf\xc0\xf3\xfc\x33\x00";

   # use utf8, strict vars subs
   $^H |= 0x00800600;

   # use feature
   $^H{feature_switch} =
   $^H{feature_say}    =
   $^H{feature_state}  = 1;
}

1;

=back

=head1 THERE IS NO 'no common::sense'!!!! !!!! !!

This module doesn't offer an unimport. First of all, it wastes even more
memory, second, and more importantly, who with even a bit of common sense
would want no common sense?

=head1 STABILITY AND FUTURE VERSIONS

Future versions might change just about everything in this module. We
might test our modules and upload new ones working with newer versions of
this module, and leave you standing in the rain because we didn't tell
you. In fact, we did so when switching from 1.0 to 2.0, which enabled gobs
of warnings, and made them FATAL on top.

Maybe we will load some nifty modules that try to emulate C<say> or so
with perls older than 5.10 (this module, of course, should work with older
perl versions - supporting 5.8 for example is just common sense at this
time. Maybe not in the future, but of course you can trust our common
sense to be consistent with, uhm, our opinion).

=head1 WHAT OTHER PEOPLE HAD TO SAY ABOUT THIS MODULE

apeiron

   "... wow"
   "I hope common::sense is a joke."

crab

   "i wonder how it would be if joerg schilling wrote perl modules."

Adam Kennedy

   "Very interesting, efficient, and potentially something I'd use all the time."
   [...]
   "So no common::sense for me, alas."

H.Merijn Brand

   "Just one more reason to drop JSON::XS from my distribution list"

Pista Palo

   "Something in short supply these days..."

Steffen Schwigon

   "This module is quite for sure *not* just a repetition of all the other
   'use strict, use warnings'-approaches, and it's also not the opposite.
   [...] And for its chosen middle-way it's also not the worst name ever.
   And everything is documented."

BKB

   "[Deleted - thanks to Steffen Schwigon for pointing out this review was
   in error.]"

Somni

   "the arrogance of the guy"
   "I swear he tacked somenoe else's name onto the module
   just so he could use the royal 'we' in the documentation"

Anonymous Monk

   "You just gotta love this thing, its got META.json!!!"

dngor

   "Heh.  '"<elmex at ta-sa.org>"'  The quotes are semantic
   distancing from that e-mail address."

Jerad Pierce

   "Awful name (not a proper pragma), and the SYNOPSIS doesn't tell you
   anything either. Nor is it clear what features have to do with "common
   sense" or discipline."

acme

   "THERE IS NO 'no common::sense'!!!! !!!! !!"

apeiron (meta-comment about us commenting^Wquoting his comment)

   "How about quoting this: get a clue, you fucktarded amoeba."

quanth

   "common sense is beautiful, json::xs is fast, Anyevent, EV are fast and
   furious. I love mlehmannware ;)"

apeiron

   "... it's mlehmann's view of what common sense is. His view of common
   sense is certainly uncommon, insofar as anyone with a clue disagrees
   with him."

apeiron (another meta-comment)

   "apeiron wonders if his little informant is here to steal more quotes"

ew73

   "... I never got past the SYNOPSIS before calling it shit."

=head1 FREQUQNTLY ASKED QUESTIONS

Or frequently-come-up confusions.

=over 4

=item Is this module meant to be serious?

Yes, we would have put it under the C<Acme::> namespace otherwise.

=item But the manpage is written in a funny/stupid/... way?

This was meant to make it clear that our common sense is a subjective
thing and other people can use their own notions, taking the steam out
of anybody who might be offended (as some people are always offended no
matter what you do).

This was a failure.

But we hope the manpage still is somewhat entertaining even though it
explains boring rationale.

=item Why do you impose your conventions on my code?

For some reason people keep thinking that C<common::sense> imposes
process-wide limits, even though the SYNOPSIS makes it clear that it works
like other similar modules - only on the scope that uses them.

So, no, we don't - nobody is forced to use this module, and using a module
that relies on common::sense does not impose anything on you.

=item Why do you think only your notion of common::sense is valid?

Well, we don't, and have clearly written this in the documentation to
every single release. We were just faster than anybody else w.r.t. to
grabbing the namespace.

=item But everybody knows that you have to use strict and use warnings,
why do you disable them?

Well, we don't do this either - we selectively disagree with the
usefulness of some warnings over others. This module is aimed at
experienced Perl programmers, not people migrating from other languages
who might be surprised about stuff such as C<undef>. On the other hand,
this does not exclude the usefulness of this module for total newbies, due
to its strictness in enforcing policy, while at the same time not limiting
the expresive power of perl.

This module is considerably I<more> strict than the canonical C<use
strict; use warnings>, as it makes all its warnings fatal in nature, so
you can not get away with as many things as with the canonical approach.

This was not implemented in version 1.0 because of the daunting number
of warning categories and the difficulty in getting exactly the set of
warnings you wish (i.e. look at the SYNOPSIS in how complicated it is to
get a specific set of warnings - it is not reasonable to put this into
every module, the maintainance effort would be enourmous).

=item But many modules C<use strict> or C<use warnings>, so the memory
savings do not apply?

I am suddenly so sad.

But yes, that's true. Fortunately C<common::sense> still uses only a
miniscule amount of RAM.

=item But it adds another dependency to your modules!

It's a fact, yeah. But it's trivial to install, most popular modules have
many more dependencies and we consider dependencies a good thing - it
leads to better APIs, more thought about interworking of modules and so
on.

=item Why do you use JSON and not YAML for your META.yml?

This is not true - YAML supports a large subset of JSON, and this subset
is what META.yml is written in, so it would be correct to say "the
META.yml is written in a common subset of YAML and JSON".

The META.yml follows the YAML, JSON and META.yml specifications, and is
correctly parsed by CPAN, so if you have trouble with it, the problem is
likely on your side.

=item But! But!

Yeah, we know.

=back

=head1 AUTHOR

 Marc Lehmann <schmorp@schmorp.de>
 http://home.schmorp.de/

 Robin Redeker, "<elmex at ta-sa.org>".

=cut

Revision:	1.29
Committed:	Mon Dec 21 09:11:36 2009 UTC (14 years, 5 months ago) by root
Branch:	MAIN
Changes since 1.28:	+12 -2 lines
Log Message:	* empty log message *
#	User	Rev	Content
1	root	1.1	=head1 NAME
2
3			common::sense - save a tree AND a kitten, use common::sense!
4
5			=head1 SYNOPSIS
6
7			use common::sense;
8
9	root	1.19	# supposed to be the same, with much lower memory usage, as:
10	root	1.1	#
11	root	1.25	# use utf8;
12	root	1.1	# use strict qw(vars subs);
13			# use feature qw(say state switch);
14			# no warnings;
15	root	1.15	# use warnings qw(FATAL closed threads internal debugging pack substr malloc
16	root	1.24	# portable prototype inplace io pipe unpack regexp
17	root	1.25	# deprecated exiting glob digit printf layer
18	root	1.15	# reserved parenthesis taint closure semicolon);
19	root	1.24	# no warnings qw(exec newline unopened);
20	root	1.1
21			=head1 DESCRIPTION
22
23			This module implements some sane defaults for Perl programs, as defined by
24	root	1.16	two typical (or not so typical - use your common sense) specimens of Perl
25	root	1.21	coders. In fact, after working out details on which warnings and strict
26			modes to enable and make fatal, we found that we (and our code written so
27			far, and others) fully agree on every option, even though we never used
28			warnings before, so it seems this module indeed reflects a "common" sense
29			among some long-time Perl coders.
30	root	1.1
31	root	1.22	The basic philosophy behind the choices made in common::sense can be
32			summarised as: "enforcing strict policies to catch as many bugs as
33			possible, while at the same time, not limiting the expressive power
34			available to the programmer".
35
36	root	1.29	Two typical examples of how this philosophy is applied in practise is the
37			handling of uninitialised and malloc warnings:
38
39			=over 4
40
41			=item I<uninitialised>
42	root	1.22
43			C<undef> is a well-defined feature of perl, and enabling warnings for
44			using it rarely catches any bugs, but considerably limits you in what you
45			can do, so uninitialised warnings are disabled.
46
47	root	1.29	=item I<malloc>
48
49	root	1.22	Freeing something twice on the C level is a serious bug, usually causing
50			memory corruption. It often leads to side effects much later in the
51			program and there are no advantages to not reporting this, so malloc
52			warnings are fatal by default.
53
54	root	1.29	=back
55
56	root	1.22	What follows is a more thorough discussion of what this module does,
57			and why it does it, and what the advantages (and disadvantages) of this
58			approach are.
59
60	root	1.29	=head1 RATIONALE
61
62	root	1.1	=over 4
63
64	root	1.25	=item use utf8
65
66			While it's not common sense to write your programs in UTF-8, it's quickly
67	root	1.26	becoming the most common encoding, is the designated future default
68			encoding for perl sources, and the most convenient encoding available
69			(you can do really nice quoting tricks...). Experience has shown that our
70			programs were either all pure ascii or utf-8, both of which will stay the
71			same.
72	root	1.25
73			There are few drawbacks to enabling UTF-8 source code by default (mainly
74			some speed hits due to bugs in older versions of perl), so this module
75			enables UTF-8 source code encoding by default.
76
77	root	1.1	=item use strict qw(subs vars)
78
79			Using C<use strict> is definitely common sense, but C<use strict
80	root	1.11	'refs'> definitely overshoots its usefulness. After almost two
81	root	1.1	decades of Perl hacking, we decided that it does more harm than being
82			useful. Specifically, constructs like these:
83
84			@{ $var->[0] }
85
86	root	1.4	Must be written like this (or similarly), when C<use strict 'refs'> is in
87			scope, and C<$var> can legally be C<undef>:
88	root	1.1
89			@{ $var->[0] \|\| [] }
90
91			This is annoying, and doesn't shield against obvious mistakes such as
92	root	1.11	using C<"">, so one would even have to write (at least for the time
93			being):
94	root	1.1
95	root	1.18	@{ defined $var->[0] ? $var->[0] : [] }
96	root	1.1
97			... which nobody with a bit of common sense would consider
98	root	1.18	writing: clear code is clearly something else.
99	root	1.11
100			Curiously enough, sometimes perl is not so strict, as this works even with
101			C<use strict> in scope:
102	root	1.1
103			for (@{ $var->[0] }) { ...
104
105	root	1.15	If that isn't hypocrisy! And all that from a mere program!
106
107	root	1.1
108			=item use feature qw(say state given)
109
110			We found it annoying that we always have to enable extra features. If
111			something breaks because it didn't anticipate future changes, so be
112	root	1.11	it. 5.10 broke almost all our XS modules and nobody cared either (or at
113	root	1.15	least I know of nobody who really complained about gratuitous changes -
114			as opposed to bugs).
115	root	1.11
116			Few modules that are not actively maintained work with newer versions of
117			Perl, regardless of use feature or not, so a new major perl release means
118			changes to many modules - new keywords are just the tip of the iceberg.
119
120	root	1.15	If your code isn't alive, it's dead, Jim - be an active maintainer.
121
122	root	1.22	But nobody forces you to use those extra features in modules meant for
123			older versions of perl - common::sense of course works there as well.
124			There is also an important other mode where having additional features by
125			default is useful: commandline hacks and internal use scripts: See "much
126			reduced typing", below.
127
128	root	1.15
129	root	1.16	=item no warnings, but a lot of new errors
130	root	1.15
131			Ah, the dreaded warnings. Even worse, the horribly dreaded C<-w>
132			switch: Even though we don't care if other people use warnings (and
133			certainly there are useful ones), a lot of warnings simply go against the
134			spirit of Perl.
135
136			Most prominently, the warnings related to C<undef>. There is nothing wrong
137			with C<undef>: it has well-defined semantics, it is useful, and spitting
138			out warnings you never asked for is just evil.
139
140	root	1.16	The result was that every one of our modules did C<no warnings> in the
141			past, to avoid somebody accidentally using and forcing his bad standards
142			on our code. Of course, this switched off all warnings, even the useful
143			ones. Not a good situation. Really, the C<-w> switch should only enable
144			warnings for the main program only.
145	root	1.15
146			Funnily enough, L<perllexwarn> explicitly mentions C<-w> (and not in a
147			favourable way, calling it outright "wrong"), but standard utilities, such
148			as L<prove>, or MakeMaker when running C<make test>, still enable them
149			blindly.
150
151	root	1.16	For version 2 of common::sense, we finally sat down a few hours and went
152			through I<every single warning message>, identifiying - according to
153			common sense - all the useful ones.
154	root	1.15
155			This resulted in the rather impressive list in the SYNOPSIS. When we
156			weren't sure, we didn't include the warning, so the list might grow in
157			the future (we might have made a mistake, too, so the list might shrink
158	root	1.16	as well).
159	root	1.15
160			Note the presence of C<FATAL> in the list: we do not think that the
161			conditions caught by these warnings are worthy of a warning, we I<insist>
162	root	1.16	that they are worthy of I<stopping> your program, I<instantly>. They are
163			I<bugs>!
164	root	1.15
165			Therefore we consider C<common::sense> to be much stricter than C<use
166			warnings>, which is good if you are into strict things (we are not,
167			actually, but these things tend to be subjective).
168
169			After deciding on the list, we ran the module against all of our code that
170			uses C<common::sense> (that is almost all of our code), and found only one
171			occurence where one of them caused a problem: one of elmex's (unreleased)
172			modules contained:
173
174			$fmt =~ s/([^\s\[])\[( [^\]] )\]/\x0$1\x1$2\x0/xgo;
175
176			We quickly agreed that indeed the code should be changed, even though it
177			happened to do the right thing when the warning was switched off.
178
179	root	1.11
180	root	1.22	=item much reduced typing
181
182			Especially with version 2.0 of common::sense, the amount of boilerplate
183			code you need to add to gte I<this> policy is daunting. Nobody would write
184			this out in throwaway scripts, commandline hacks or in quick internal-use
185			scripts.
186
187			By using common::sense you get a defined set of policies (ours, but maybe
188			yours, too, if you accept them), and they are easy to apply to your
189			scripts: typing C<use common::sense;> is even shorter than C<use warnings;
190			use strict; use feature ...>.
191
192			And you can immediately use the features of your installed perl, which
193			is more difficult in code you release, but not usually an issue for
194			internal-use code (downgrades of your production perl should be rare,
195			right?).
196
197
198	root	1.11	=item mucho reduced memory usage
199
200			Just using all those pragmas mentioned in the SYNOPSIS together wastes
201			<blink>I<< B<776> kilobytes >></blink> of precious memory in my perl, for
202			I<every single perl process using our code>, which on our machines, is a
203			lot. In comparison, this module only uses I<< B<four> >> kilobytes (I even
204			had to write it out so it looks like more) of memory on the same platform.
205	root	1.1
206			The money/time/effort/electricity invested in these gigabytes (probably
207			petabytes globally!) of wasted memory could easily save 42 trees, and a
208			kitten!
209
210	root	1.11	Unfortunately, until everybods applies more common sense, there will still
211			often be modules that pull in the monster pragmas. But one can hope...
212
213	root	1.1	=cut
214
215	root	1.2	package common::sense;
216	root	1.1
217	root	1.25	our $VERSION = '3.0';
218	root	1.15
219	root	1.19	# paste this into perl to find bitmask
220	root	1.1
221	root	1.13	# no warnings;
222	root	1.24	# use warnings qw(FATAL closed threads internal debugging pack substr malloc portable prototype
223	root	1.16	# inplace io pipe unpack regexp deprecated exiting glob digit printf
224	root	1.25	# layer reserved parenthesis taint closure semicolon);
225	root	1.24	# no warnings qw(exec newline unopened);
226	root	1.14	# BEGIN { warn join "", map "\\x$_", unpack "(H2)*", ${^WARNING_BITS}; exit 0 };
227	root	1.13
228			# overload should be included
229
230	root	1.2	sub import {
231	root	1.13	# verified with perl 5.8.0, 5.10.0
232	root	1.25	${^WARNING_BITS} ^= ${^WARNING_BITS} ^ "\xfc\x3f\x33\x00\x0f\xf3\xcf\xc0\xf3\xfc\x33\x00";
233	root	1.3
234	root	1.25	# use utf8, strict vars subs
235			$^H \|= 0x00800600;
236	root	1.3
237			# use feature
238			$^H{feature_switch} =
239			$^H{feature_say} =
240			$^H{feature_state} = 1;
241	root	1.1	}
242
243			1;
244
245			=back
246
247	root	1.5	=head1 THERE IS NO 'no common::sense'!!!! !!!! !!
248	root	1.4
249			This module doesn't offer an unimport. First of all, it wastes even more
250			memory, second, and more importantly, who with even a bit of common sense
251			would want no common sense?
252
253	root	1.5	=head1 STABILITY AND FUTURE VERSIONS
254
255			Future versions might change just about everything in this module. We
256			might test our modules and upload new ones working with newer versions of
257			this module, and leave you standing in the rain because we didn't tell
258	root	1.15	you. In fact, we did so when switching from 1.0 to 2.0, which enabled gobs
259			of warnings, and made them FATAL on top.
260	root	1.5
261	root	1.15	Maybe we will load some nifty modules that try to emulate C<say> or so
262			with perls older than 5.10 (this module, of course, should work with older
263			perl versions - supporting 5.8 for example is just common sense at this
264			time. Maybe not in the future, but of course you can trust our common
265			sense to be consistent with, uhm, our opinion).
266	root	1.11
267			=head1 WHAT OTHER PEOPLE HAD TO SAY ABOUT THIS MODULE
268
269			apeiron
270
271			"... wow"
272			"I hope common::sense is a joke."
273
274			crab
275	root	1.5
276	root	1.11	"i wonder how it would be if joerg schilling wrote perl modules."
277	root	1.7
278	root	1.17	Adam Kennedy
279
280			"Very interesting, efficient, and potentially something I'd use all the time."
281			[...]
282			"So no common::sense for me, alas."
283
284	root	1.11	H.Merijn Brand
285
286			"Just one more reason to drop JSON::XS from my distribution list"
287	root	1.7
288			Pista Palo
289
290			"Something in short supply these days..."
291
292			Steffen Schwigon
293
294			"This module is quite for sure not just a repetition of all the other
295			'use strict, use warnings'-approaches, and it's also not the opposite.
296			[...] And for its chosen middle-way it's also not the worst name ever.
297			And everything is documented."
298
299			BKB
300
301			"[Deleted - thanks to Steffen Schwigon for pointing out this review was
302			in error.]"
303
304			Somni
305
306			"the arrogance of the guy"
307			"I swear he tacked somenoe else's name onto the module
308			just so he could use the royal 'we' in the documentation"
309
310	root	1.23	Anonymous Monk
311
312			"You just gotta love this thing, its got META.json!!!"
313
314	root	1.7	dngor
315
316			"Heh. '"<elmex at ta-sa.org>"' The quotes are semantic
317			distancing from that e-mail address."
318
319			Jerad Pierce
320
321			"Awful name (not a proper pragma), and the SYNOPSIS doesn't tell you
322			anything either. Nor is it clear what features have to do with "common
323			sense" or discipline."
324
325			acme
326
327			"THERE IS NO 'no common::sense'!!!! !!!! !!"
328
329	root	1.15	apeiron (meta-comment about us commenting^Wquoting his comment)
330	root	1.12
331	root	1.23	"How about quoting this: get a clue, you fucktarded amoeba."
332	root	1.12
333	root	1.20	quanth
334
335	root	1.23	"common sense is beautiful, json::xs is fast, Anyevent, EV are fast and
336			furious. I love mlehmannware ;)"
337	root	1.20
338	root	1.28	apeiron
339
340			"... it's mlehmann's view of what common sense is. His view of common
341			sense is certainly uncommon, insofar as anyone with a clue disagrees
342			with him."
343
344	root	1.27	apeiron (another meta-comment)
345
346			"apeiron wonders if his little informant is here to steal more quotes"
347
348			ew73
349
350			"... I never got past the SYNOPSIS before calling it shit."
351
352	root	1.19	=head1 FREQUQNTLY ASKED QUESTIONS
353
354			Or frequently-come-up confusions.
355
356			=over 4
357
358			=item Is this module meant to be serious?
359
360			Yes, we would have put it under the C<Acme::> namespace otherwise.
361
362			=item But the manpage is written in a funny/stupid/... way?
363
364			This was meant to make it clear that our common sense is a subjective
365			thing and other people can use their own notions, taking the steam out
366			of anybody who might be offended (as some people are always offended no
367			matter what you do).
368
369			This was a failure.
370
371			But we hope the manpage still is somewhat entertaining even though it
372			explains boring rationale.
373
374			=item Why do you impose your conventions on my code?
375
376			For some reason people keep thinking that C<common::sense> imposes
377			process-wide limits, even though the SYNOPSIS makes it clear that it works
378			like other similar modules - only on the scope that uses them.
379
380			So, no, we don't - nobody is forced to use this module, and using a module
381			that relies on common::sense does not impose anything on you.
382
383			=item Why do you think only your notion of common::sense is valid?
384
385			Well, we don't, and have clearly written this in the documentation to
386			every single release. We were just faster than anybody else w.r.t. to
387			grabbing the namespace.
388
389			=item But everybody knows that you have to use strict and use warnings,
390			why do you disable them?
391
392			Well, we don't do this either - we selectively disagree with the
393			usefulness of some warnings over others. This module is aimed at
394			experienced Perl programmers, not people migrating from other languages
395	root	1.22	who might be surprised about stuff such as C<undef>. On the other hand,
396			this does not exclude the usefulness of this module for total newbies, due
397			to its strictness in enforcing policy, while at the same time not limiting
398			the expresive power of perl.
399
400			This module is considerably I<more> strict than the canonical C<use
401			strict; use warnings>, as it makes all its warnings fatal in nature, so
402			you can not get away with as many things as with the canonical approach.
403	root	1.19
404			This was not implemented in version 1.0 because of the daunting number
405			of warning categories and the difficulty in getting exactly the set of
406			warnings you wish (i.e. look at the SYNOPSIS in how complicated it is to
407			get a specific set of warnings - it is not reasonable to put this into
408			every module, the maintainance effort would be enourmous).
409
410			=item But many modules C<use strict> or C<use warnings>, so the memory
411			savings do not apply?
412
413			I am suddenly so sad.
414
415			But yes, that's true. Fortunately C<common::sense> still uses only a
416			miniscule amount of RAM.
417
418			=item But it adds another dependency to your modules!
419
420			It's a fact, yeah. But it's trivial to install, most popular modules have
421			many more dependencies and we consider dependencies a good thing - it
422			leads to better APIs, more thought about interworking of modules and so
423			on.
424
425	root	1.22	=item Why do you use JSON and not YAML for your META.yml?
426
427			This is not true - YAML supports a large subset of JSON, and this subset
428			is what META.yml is written in, so it would be correct to say "the
429			META.yml is written in a common subset of YAML and JSON".
430
431			The META.yml follows the YAML, JSON and META.yml specifications, and is
432			correctly parsed by CPAN, so if you have trouble with it, the problem is
433			likely on your side.
434
435	root	1.19	=item But! But!
436
437			Yeah, we know.
438
439			=back
440
441	root	1.1	=head1 AUTHOR
442
443			Marc Lehmann <schmorp@schmorp.de>
444			http://home.schmorp.de/
445
446	root	1.4	Robin Redeker, "<elmex at ta-sa.org>".
447
448	root	1.1	=cut
449