=pod

=head1 NAME

sanity - The ONLY meta pragma you'll ever need!

=head1 VERSION

version 0.92

=head1 SYNOPSIS

   use sanity;
   use sanity 'strictures';
   use sanity 'Modern::Perl';
   
   use sanity qw(
      strictures -warnings/uninitialized/FATAL
      NO:autovivification NO:autovivification/store 
      PRINT_PRAGMA_HASH
   );
   use sanity '!0*b^Npow{8T7_yZt<?cT6/?ZCO=Y0LV_Duoc';  # Safer ASCII version
   use sanity '¡0ǲ鵆㤧뱞⡫瘑빸ን둈댬嚝⠨舁聼䮋';  # Shorter UTF8 version

=head1 DESCRIPTION

Modern::Perl?  common::sense?  no nonsense?  use latest?

Everybody has their own opinion on what pragmas and modules are "required"
for every person to use.  These opinions turn into "personal pragmas", so that
people don't have to type several C<use> lines of header in front of every module
they write.

Personal opinions and pragmas don't really belong in the CPAN namespace.  (It's 
CPAN, not Personal PAN.  If you want a Personal PAN, go call Pizza Hut.)  But
copying code on potentially hundreds of modules doesn't make sense, either.

That was my mentality when I had a personal opinion of my own.  Why repeat the same
problem like everybody else?

This "sanity" module attempts to level the playing field by making it a
B<customizable> personal pragma, allowing you to both reduce the code needed and 
still implement all of the modules/pragmas you need.

As an illustration to what it's capable of, this pragma will emulate all of the
other personal pragmas, most of them 100% working exactly how they do it.

=head1 PARAMETERS

Sanity's parameters fall into three types: flags, aliases, and hashes.  (Oh my!)

=head2 Flags and Aliases

Flags are single pragma/module declarations, strict/warning flags, or other
items that need flags.  Aliases are merely one or more flags, grouped
together to better emulate the pragma/module's functionality.

Let's start off with an example:

   # These three statements do the same thing as...
   use Modern::Perl;
   use sanity 'Modern::Perl';
   use sanity qw(strict warnings mro/dfs feature IO::File IO::Handle);
   
   # ...these statements
   use strict;
   use warnings;
   use mro 'dfs';
   use feature ':all';
   use IO::File;
   use IO::Handle;

Basically, it does the same thing as the meta pragma L<Modern::Perl>, except
you actually don't need that module for it to work.  While there is some magic
to make sure, say, C<feature> gets loaded with various versions of Perl, it typically
just works using a standard C<import> call.  The C<strict> and C<warnings> flags
are combined aliases that enable all of the warnings that they would do via a standard
call.

=head3 Negating flags/aliases

You can turn off flags in the statement:

   use sanity qw(Modern::Perl -mro/dfs);

This does the same thing as above, except it doesn't import the C<mro> pragma.  You
can negate any flag, including combined aliases, as long as it makes sense.  In other
words, you need a positive included before you can negate something.

=head3 NO:* flags/aliases

Some pragmas work by using the C<B<unimport>> function, so that the English makes sense.
To keep that syntax, these pragmas are included with a C<NO:> prefix:

   use sanity 'NO:multidimensional';
   use sanity 'NO:indirect/FATAL';

This will run the C<unimport> function on these pragmas, even though sanity was called
via the C<import> function (via C<use>).

=head3 Perl versions

Sanity also supports Perl versions as a special kind of alias to specify minimum Perl
versions:

   # These are all the same:
   use v5.10.1;
   use sanity 'v5.10.1';
   use sanity v5.10.1;  # as a VSTRING
   use sanity 5.10.1;   # works too
   
   # Upgrade the Perl version of your favorite pragma
   use sanity qw(NO:nonsense v5.12);

Note that the version must be at least v5.8.  This should be fine for most people.  (If 
I get a ticket requesting support for a Perl version older than one released in 2002, I
will hunt you down and break your keyboard in half.)

=head3 The Default

What does C<sanity> do without any parameters?  Why my personal preference, of course :)
It's listed in the C<meta pragma> section of the L<LIST OF FLAGS> below.  I detail the
reasons behind my choices L<here|sanity::sanity>.

=head2 Hashes

So, there's all of these flags, but unless you're using one of the combined aliases,
typing them all out is usually just as much (or more) code as the several lines of C<use>
statements.  Well, they are all flags so that it fits into a giant bitmap, and that
bitmap can be compressed into a large ASCII (or UTF-8) "number".

This number can be calculated using the flag C<PRINT_PRAGMA_HASH>:

   # This is merely the definition of uni::perl
   use sanity (qw(
      v5.10 strict feature/5.10
   ), (
      map { "warnings/$_/FATAL" } qw(closed threads internal debugging pack substr malloc
      unopened portable prototype inplace io pipe unpack regexp deprecated exiting glob
      digit printf utf8 layer reserved parenthesis taint closure semicolon)
   ), qw(
      -warnings/exec/FATAL
      -warnings/newline/FATAL
      utf8
      open/utf8
      open/std
      mro/c3
      Carp
   ), 'PRINT_PRAGMA_HASH');
   
   # Outputs:
   # use sanity '!04[D{9Fhfqc-7m738S4HK6B#D5=v{,T$(0)F5i';  # Safer ASCII version
   # use sanity '¡05༕ቑ釩腜쥸봱楇䐍퇥熠ᾯ緻褻真堩';  # Shorter UTF8 version

You can use that hash as the output illustrates without having to type out the entire big
set of commands or flags.

=head2 Other Meta Pragmas

Have your own set that is too long, and you don't like the ugliness of the hash?  Send me
your suggestion and I'll probably add it in.

=head1 CAVEATS

=head2 'NO:' ne '-'

A C<NO:> flag is NOT the same as negating a flag!  You also cannot remove the C<NO:>
from a flag, as it's part of the name of the flag, not a special modifier.

   # These two are NOT the same!
   use sanity 'NO:indirect';  # runs indirect->unimport()
   use sanity '-indirect';    # Dies, as there is no such flag/alias
   
   # This runs through the strictures alias and runs autovivification->unimport()
   use sanity qw(strictures NO:autovivification);
   
   # This runs through the strictures alias WITHOUT running indirect->unimport()
   use sanity qw(strictures -NO:indirect);
   
   use sanity '-indirect';    # This isn't what you want...
   no  sanity 'NO:indirect';  # ...you really meant to do this...
   use indirect;              # ...but this is better

=head2 Special clearing of strict/warnings

Since most people want exactly the strictness and warnings they specify, sanity will
clear these out first before running through the list.

   # This...
   use sanity qw(strict -strict/vars);
   
   # ...is the same as this...
   no strict;
   use strict qw(subs refs);

Also, some special magic is in place to ensure that newer warnings/features aren't
fatal to older Perls.  See L<https://rt.perl.org/rt3/Ticket/Display.html?id=112920>.

=head2 "Author" pragmas

Certain pragmas really only exist to make sure the code is designed right.  These 
pragmas are deemed "optional" by C<sanity>.  In other words, if the user doesn't
have them, it will just silently ignore them and move on.  If C<sanity> thinks your
an author/coder of the module itself (.git/svn/$ENV checks), it will give you a
warning that they are missing, but move on.

The following modules don't "instadie".  Modules that fall under this list don't
change the nature of how Perl works, or would let you do something that would
normally fatally error.

   overloading
   autovivification
   indirect
   multidimensional
   bareword::filehandles
   criticism

   # (autovivification probably shouldn't be here, since it actually
   # prevents autoviv, but it's generally used as an author tool.)

This feature was borrowed from L<strictures> and tweaked.   

=head1 LIST OF FLAGS

=head2 Emulation of "meta pragmas"

   ex::caution:
      strict
      warnings
   NO:crap:  # Same as above
   latest:
      strict
      warnings
      feature
   sane:
      strict
      warnings
      feature
      utf8
   NO:nonsense:
      strict
      warnings
      true
      namespace::autoclean
   Modern::Perl:
      strict
      warnings
      mro 'dfs'
      feature
      IO::File
      IO::Handle
   strictures: (without the 5.8.4 checks; that crap is old)
      v5.8.4 (forced, to make sure things work)
      strict
      warnings FATAL => 'all'
      no indirect 'fatal'
      no multidimensional
      no bareword::filehandles
   common::sense: (without the "memory usage" BS)
      utf8
      strict qw(subs vars)
      feature qw(say state switch)
      no warnings
      warnings FATAL => qw(closed threads internal debugging pack malloc portable prototype
                           inplace io pipe unpack deprecated glob digit printf
                           layer reserved taint closure semicolon)
      no warnings qw(exec newline unopened);
   uni::perl: (ditto)
      v5.10
      strict
      feature qw(say state switch)
      no warnings
      warnings qw(FATAL closed threads internal debugging pack substr malloc
                      unopened portable prototype inplace io pipe unpack regexp
                      deprecated exiting glob digit printf utf8 layer
                      reserved parenthesis taint closure semicolon)
      no warnings qw(exec newline)
      utf8
      open (:utf8 :std)
      mro 'c3'
      Carp
   sanity:
      v5.10.1
      utf8
      open (:utf8 :std)
      mro 'c3'
      strict qw(subs vars)
      no strict 'refs'
      warnings FATAL => 'all'
      no warnings qw(uninitialized)
      feature
      no autovivification qw(fetch exists delete store strict)
      no indirect 'fatal'
      no multidimensional
      namespace::sweep
   perl5i::0 / 1 / 2 / latest:
      [the real module] (the pragma is too insane to try to duplicate here)
   Acme::Very::Modern::Perl:  (a joke, but it's still here all the same)
      strict
      warnings
      mro 'c3'
      feature
      IO::File
      IO::Handle
      utf8
      open (:utf8 :std)
      no warnings
      warnings FATAL => qw(closed threads internal debugging pack malloc portable prototype
                           inplace io pipe unpack deprecated glob digit printf
                           layer reserved taint closure semicolon)
      no warnings qw(exec newline unopened);
      perl5i::latest
      Toolkit
      Carp

=head2 Other flags/aliases

   strict/* => strict '[whatever]'        # supports all flags
   strict   => strict qw(refs subs vars)

   # other "hints"
   integer
   locale
   bytes
   re/taint
   re/eval
   filetest
   utf8
   NO:overloading
   
   warnings/*       => warnings NONFATAL => '[whatever]'  # supports all flags, multi or not
   warnings/*/FATAL => warnings    FATAL => '[whatever]'  # supports all flags; FATAL trumps NONFATAL
   warnings         => warnings NONFATAL => 'all'
   warnings/FATAL   => warnings    FATAL => 'all'
   
   feature/*        => feature '[whatever]'  # supports all flags
   feature/5.##     => # similar to feature enabling via 'use v5.##'; major version only
   feature/5.9.5    => # also exists, just like feature/5.10
   feature          => feature ':all'  # not exactly, but in spirit
   
   # Perl versions, described above
   v5.##.##
   
   # autodie
   autodie/* => autodie ':[whatever]'  # supports all _category_ flags, like all, io, shm, etc.
                                       # (Will expand if requested, but I don't want to waste
                                       # all of that bit space right now.)
   autodie   => autodie ':default'
   
   # other CORE pragmas
   bigint
   bignum
   bigrat
   charnames
   charnames/short
   charnames/full
   encoding::warnings
   encoding::warnings/FATAL
   mro/dfs                    # default for 'mro'
   mro/c3
   open/*

   # namespace cleaners
   namespace::clean       # included last; adds -except => 'meta'
   namespace::functions   # included last                                    
   namespace::autoclean
   namespace::sweep

   # others
   NO:autovivification/*
   NO:autovivification => no autovivification qw(fetch exists delete)

   criticism/*
   criticism   => criticism 'gentle'

   perl5i::0
   perl5i::1
   perl5i::2
   perl5i::3
   perl5i::latest
   
   NO:indirect
   NO:indirect/global
   NO:indirect/fatal
   NO:multidimensional
   NO:bareword::filehandles
   
   subs::auto
   utf8::all
   IO::File
   IO::Handle
   IO::All
   Carp
   vendorlib
   true
   autolocale
   Toolkit

Am I missing something?  Let me know.

=head1 TODO

Actually need to write sanity::sanity POD.

=head1 AUTHOR

Brendan Byrd <BBYRD@CPAN.org>

=head1 COPYRIGHT AND LICENSE

This software is Copyright (c) 2012 by Brendan Byrd.

This is free software, licensed under:

  The Artistic License 2.0 (GPL Compatible)

