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

SYNOPSIS
     use common::sense;

     # roughly the same as, with much lower memory usage:
     #
     # use strict qw(vars subs);
     # use feature qw(say state switch);
     # no warnings;

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.

    no warnings
        The dreaded warnings. Even worse, the horribly dreaded "-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 "undef". There is nothing wrong with "undef": it has well-defined
        semantics, it is useful, and spitting out warnings you never asked
        for is just evil.

        So every module needs "no warnings" to avoid somebody accidentally
        using "-w" and forcing his bad standards on our code. No will do.

        Funnily enough, perllexwarn explicitly mentions "-w" (and not in a
        favourable way), but standard utilities, such as prove, or MakeMaker
        when running "make test" enable them blindly.

    use strict qw(subs vars)
        Using "use strict" is definitely common sense, but "use strict
        'refs'" definitely overshoots it's 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 "use strict 'refs'"
        is in scope, and $var can legally be "undef":

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

        This is annoying, and doesn't shield against obvious mistakes such
        as using "", so one would even have to write:

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

        ... which nobody with a bit of common sense would consider writing.
        Curiously enough, sometimes, perl is not so strict, as this works
        even with "use strict" in scope:

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

        If that isnt hipocrasy! And all that from a mere program!

    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
        - and few modules that are no longer maintained work with newer
        versions of Perl, regardless of use feature.

        If your code isn't alive, it's dead, jim.

    much less memory
        Just using all those pragmas together waste <blink>*776
        kilobytes*</blink> of precious memory in my perl, for *every single
        perl process using our code*, which on our machines, is a lot. In
        comparison, this module only uses *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!

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?

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.

    Most likely, we will pick a few useful warnings, instead of just
    disabling all of them. And maybe we will load some nifty modules that
    try to emulate "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).

WHAT OTHER PEOPLE HAVE TO SAY ABOUT THIS MODULE
    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"

    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'!!!! !!!! !!"

    crab

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

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

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