Instead of using explicit while(){} and for(){} loops, I tend to use perl's built-in looping constructs. 

# read
use Path::Tiny;
my @words = ( path($filename)->slurp ) =~ /^.+$/gm;

[download]

or 

# optional read without Path::Tiny
my @words = do { local(@ARGV, $/) = $filename; <> =~ /^.+$/gm };

# or
my @words = do { local(@ARGV, $/) = $filename; split /\n/, <> };

[download]

and for write 

# write
use Path::Tiny;
use List::Util qw( uniq );
path($filename)->spew(join "\n", uniq(@words), '');

[download]

The regex on input was a win for me reading /usr/share/dict/words on my system which has over 123,000 lines in it.

General rule: Don't do things item by item when you can do multiple things at once.

In reply to Re: best way to read and save long list of words by tybalt89
in thread best way to read and save long list of words by Anonymous Monk

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.