I had a chat with my neighbor who asked me if Padre is going to be able to suggest better code constructs. His example was that some tools can sometimes recognize when a loop is unnecessary in a piece of code. I told him that it is very difficult in Perl and we already have Perl::Critic but I thought about this a bit more and came up with a few examples that I don't think Perl::Critic or any of its extensions covers but might be interesting and possible to recognize. 
my $x;
foreach $x () {}

[download]
Here I'd suggest to write it as 
foreach my $x () {}

[download]
and would explain that the $x outside the foreach loop is different from the one inside.
A more involved example would be 
@files = `ls`;

[download]
and its bigger brother: 
@files = `ls *.xml|more`;

[download]
In such code I'd suggest to use 
glob("*.xml")

[download]
Yet another example would be the extensive processing of values from @ARGV that could be replaced by the use of Getopt::Long.
Is there any module on CPAN that can already recognize such constructs and recommend something else?
Can this be done in a reasonable way?
What other constructs would you like to catch and what would you suggest instead of them?

In reply to The maybe it is better written this way tool by szabgab

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.