You may find YAPE::Regex::Explain useful for 'explaining' your regex:

use Modern::Perl;
use YAPE::Regex::Explain;

my $regex = 'outlook\s+for\s+any\s+rating|(?:rating|if\s+on\s+negative
+|Microsoft|suggesting\s+an|may\s+contain\s+statements\s+about\s+futur
+e\s+events\,|business\s+conditions\s+and\s+the)\s+outlook|guidance\s+
+(?:to\s+approve|facility)
                  |(?:authoritative|revenue\s+recognition|invaluable\s
++practical|valuable|regulatory|technical|under\s+the|staff\'s|judicia
+l|SEC|FDA|Treasury(?:\s+Department)?|specific|implementation|their|go
+vernment|any\s+ruling|college|absent|\s+his|interim|intrepretive|tran
+sition|administrative|procedural|related|applicable|accounting|defini
+tive|superceding|IRS|Internal\s+Revenue\s+Service|valued|EITF\s+accou
+nting)\s+guidance
                  |guidance\s+(?:and\s+rules|promulgated(?:\s+thereund
+er)?|in\s+SFAS)|(?:provided|issued)\s+by\s+(?:the\s+)?(?:SEC|Securiti
+es\s+and\s+Exchange\s+Commission|Internal\s+Revenue\s+Service|Secreta
+ry|United\s+States|Financial\s+Accounting)
                  |(?:other|applicable)\s+guidance\s+issued|according\
+s+to\s+the\s+guidance\s+contained|provide\s+guidance\s+to\s+directors
+|receiving\s+guidance
                  |(?:current|other)\s+guidance\s+(?:under|from)|assum
+es\s+guidance\s+of\s+(?:the|a)\s+(?:company|board|talented\s+team|com
+pensation)|guidance\s+(?:system|software|technology)';

say YAPE::Regex::Explain->new($regex)->explain;

[download]

Partial output:

...

matches as follows:
  
NODE                     EXPLANATION
----------------------------------------------------------------------
(?-imsx:                 group, but do not capture (case-sensitive)
                         (with ^ and $ matching normally) (with . not
                         matching \n) (matching whitespace and #
                         normally):
----------------------------------------------------------------------
  outlook                  'outlook'
----------------------------------------------------------------------
  \s+                      whitespace (\n, \r, \t, \f, and " ") (1 or
                           more times (matching the most amount
                           possible))
----------------------------------------------------------------------
  for                      'for'
----------------------------------------------------------------------
  \s+                      whitespace (\n, \r, \t, \f, and " ") (1 or
                           more times (matching the most amount
                           possible))
----------------------------------------------------------------------
  any                      'any'
----------------------------------------------------------------------
  \s+                      whitespace (\n, \r, \t, \f, and " ") (1 or
                           more times (matching the most amount
                           possible))
----------------------------------------------------------------------
  rating                   'rating'
----------------------------------------------------------------------
 |                        OR
----------------------------------------------------------------------
  (?:                      group, but do not capture:
----------------------------------------------------------------------
    rating                   'rating'
----------------------------------------------------------------------
   |                        OR
----------------------------------------------------------------------
    if                       'if'
----------------------------------------------------------------------
    \s+                      whitespace (\n, \r, \t, \f, and " ") (1
                             or more times (matching the most amount
                             possible))
----------------------------------------------------------------------

...

[download]

In reply to Re: Quick Question about checking what the regex does by Kenosis
in thread Quick Question about checking what the regex does by eversuhoshin

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":


  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.