You're most welcome!

Here's the regex in the grep (with two added features that should be there):

/^\Q$host\E$/;
 ^ ^      ^^
 | |      ||
 | |      |+ - End of line
 | |      + - End quote metacharacters
 | + - Begin quote metacharacters (e.g., [.*\+], etc.)
 + - Match beginning at the start of the line

[download]

If you remove the trailing $, it'll match a host name beginning with "db". Try the following with and without the trailing $ in the regex:

use warnings;
use strict;

my $host = 'db';

while (<DATA>) {
    print if /^\Q$host\E$/i;
}

__DATA__
db
db4323
dbwindows822.tp.com
db726.tp.com

[download]

Output with $:

db

[download]

This is because if forces an exact match, like $host eq 'db'.

Output without $:

db
db4323
dbwindows822.tp.com
db726.tp.com

[download]

This is becuase it's only matching the first two characters of $_ (the default scalar) against the value of $host.

Note that there's the i modifier at the end of the regex. This makes the match case-insensitive, in case you have a host like DB4323.

In reply to Re^5: If conditional checks by Kenosis
in thread If conditional checks by kitkit201

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.