[conspire] RElief: Re: CAPS - eyes hurt

[Michael Paoli]

> Date: Tue, 18 Dec 2018 15:59:20 -0800
> From: Rick Moen <rick at linuxmafia.com>
> To: conspire at linuxmafia.com
> Subject: Re: [conspire] successful install, at last
>
> Quoting Paul Zander (paulz at ieee.org):
>
>>  REPLIES BELOW, ALL IN CAPS
>
> Wow, my eyes hurt.

Ouch ...
Fortunately we have effective treatments for that, e.g. RElief can
be provided by REs - Regular Expressions ...
Which, e.g., can all be done in lovely vi(1), such as by doing:
:g/^[^a-z]*$/s/^.*[A-Z].*$/< \L&/
For those that don't quite grok vi/ex/REs:
: start ex command
  g globally (for all matching lines)
   / begin Regular Expression (RE)
    ^ start of line
     [ start of character class
      ^ negate
       a literal a
        - through
         z literal z
          ] end of character class
           * zero or more of the preceding "atom" (our character class)
            $ end of line
             / end of RE (full line containing zero lowercase chars)
              s substitute (for those lines that matched)
               / start of RE
                ^ start of line
                 . any single character
                  * zero or more of the preceding "atom" (any single char)
                   [ start of character class
                    A literal A
                     - through
                      Z literal Z
                       ] end of character class
                        . any single character
                         * zero or more of the preceding "atom" (any  
single char)
                          $ end of line
                           / end of RE (full line containing an uppercase char)
                            <  we substitute for our matched RE < and space
                              \L and everything following we lowercase it
                                & our entire matched RE
                                 / end of substitution
So that command, in vi(1), takes all lines that contain no lowercase letters
and at least one uppercase letter, and prepends < and space to the line
and changes all the uppercase letters to lowercase on that line.