ch01_02.htm

by Randal L. Schwartz and Tom Phoenix ISBN 0-596-00132-0 Third Edition, published July 2001. (See

write, faster to read, faster to debug, and faster to maintain. It
doesn't take much programming before you realize that, when the
entire subroutine is small enough to fit onscreen all at once, you
don't have to keep scrolling back and forth to see what's
going on. Also, since the number of bugs in a program is roughly
proportional to the length of the source code<a href="#FOOTNOTE-17">[17]</a> (rather than being proportional to
the program's functionality), the shorter source in Perl will
mean fewer bugs on average.
</p><blockquote class="footnote"> <a name="FOOTNOTE-17" /><p>[17]With a
sharp jump when any one section of the program exceeds the size of
your screen.</p> </blockquote>

<p>Like any language, Perl can be
"write-only" -- it's possible to write programs
that are impossible to read. But with proper care, you can avoid this
common accusation. Yes, sometimes Perl looks like line-noise to the
uninitiated, but to the seasoned Perl programmer, it looks like
checksummed line-noise with a mission in life. If you follow the
guidelines of this book, your programs should be easy to read and
easy to maintain, and they probably won't win The Obfuscated
Perl Contest.<a href="#FOOTNOTE-18">[18]</a>
</p><blockquote class="footnote"> <a name="FOOTNOTE-18" /><p>[18]An actual annual event sponsored by the
<em class="citetitle">Perl Journal </em>(at <a href="http://www.tpj.com/">http://www.tpj.com/</a> ).</p> </blockquote>

</div>
<a name="lperl3-CHP-1-SECT-2.3" /><div class="sect2">
<h3 class="sect2">1.2.3. How Did Perl Get to Be So Popular?</h3>

<p>After playing with Perl a bit, adding stuff here and there, Larry
released it to the community of Usenet readers, commonly known as
"the Net." The users on this ragtag fugitive fleet of
systems around the world (tens of thousands of them) gave him
feedback, asking for ways to do this, that, or the other thing, many
of which Larry had never envisioned his little Perl handling.
</p>

<p>But as a result, Perl grew, and grew, and grew. It grew in features.
It grew in portability. What was once a little language available on
only a couple of Unix systems has now grown to have thousands of
pages of free online documentation, dozens of books, several
mainstream Usenet newsgroups (and a dozen newsgroups and mailing
lists outside the mainstream) with an uncountable number of readers,
and implementations on nearly every system in use today -- and
don't forget this Llama book as well.
</p>

</div>
<a name="lperl3-CHP-1-SECT-2.4" /><div class="sect2">
<h3 class="sect2">1.2.4. What's Happening with Perl Now?</h3>

<p>Larry is still in charge of
<a name="INDEX-26" />Perl, although the Perl development team is
now made up of approximately thirty key people and a few hundred
others from around the world. And Perl is still growing.
</p>

<p>These days, Perl is still free for you to use. In fact, Larry
promises that it will <em class="emphasis">always</em> be free.
(He's a really nice guy; you'd like him.) So go ahead and
write code in Perl today, without worrying that there will be a
licensing fee on your program tomorrow.
</p>

<p>So, if Perl is free, who pays Larry and the other Perl developers?
Well, the majority of us contribute to Perl as a labor of love; Perl
helps us, and we help Perl. (If you ever see some way in which you
could improve Perl, we encourage you to send in your contributions,
too.) In some cases, though, a person or firm has paid someone to do
some development work. This may be because they needed some new
functionality badly enough to pay for it, or because they wanted to
make the world a better place.
</p>

<p>Larry doesn't write all of the code these days, but he still
guides the development and makes the big decisions. One of the most
important rules he's given us is this one: "Common things
should be easy; advanced things should at least be possible."
</p>

<p>Because of that rule, you can be sure that anything that you need to
do frequently will have a shortcut in Perl. In fact, by the end of
this book, you'll probably be using at least ten shortcuts in a
typical ten-line program. That is the sort of thing that makes Perl
easier to use, at the price of being harder to learn.<a name="INDEX-27" />
</p>

</div>
<a name="lperl3-CHP-1-SECT-2.5" /><div class="sect2">
<h3 class="sect2">1.2.5. What's Perl Really Good For?</h3>

<p><a name="INDEX-28" />Perl is good for quick-and-dirty
programs that you whip up in three minutes. Perl is also good for
long-and-extensive programs that will take a dozen programmers three
years to finish. Of course, you'll probably find yourself
writing many programs that take you less than an hour to complete,
from the initial plan to the fully tested code.
</p>

<p>Perl is optimized for problems which are about 90% working with text
and about 10% everything else. That description seems to fit most
programming tasks that pop up these days. In a perfect world, every
programmer could know every language; you'd always be able to
choose the best language for each project. Most of the time,
you'd choose Perl.<a href="#FOOTNOTE-19">[19]</a>
</p><blockquote class="footnote"> <a name="FOOTNOTE-19" /><p>[19]Don't just take our
word for it, though. If you want to know whether Perl is better than
language X, learn them both and try them both, then see which one you
use most often. That's the one that's best for you. In
the end, you'll understand Perl better because of your study of
language X, and vice versa, so it will be time well spent.</p>
</blockquote>

<p>Although the Web wasn't even a twinkle in Tim
Berners-Lee's eye when Larry created Perl, it was a marriage
made on the Net. Some claim that the deployment of Perl in the early
1990s permitted lots of content to be moved into HTML format very
rapidly, and the Web couldn't exist without content. Of course,
Perl is the darling language for small CGI scripting (programs run by
a web server) as well -- so much so that many of the uninformed
still make statements like "Isn't CGI just Perl?"
or "Why would you use Perl other than for CGI?" We find
those statements amusing.
</p>

</div>
<a name="lperl3-CHP-1-SECT-2.6" /><div class="sect2">
<h3 class="sect2">1.2.6. What Is Perl Not Good For?</h3>

<p>So, if it's good for so many things, what is Perl
<em class="emphasis">not</em> good for? Well, you shouldn't choose
Perl if you're trying to make an <em class="firstterm">opaque
binary</em>. That's a program that you could give away
or sell to someone who then can't see your secret algorithms in
the source, and thus can't help you to maintain or debug your
code either. When you give someone your Perl program, you'll
normally be giving them the source, not an opaque binary.
</p>

<p>If you're wishing for an opaque binary, though, we have to tell
you that they don't exist. If someone can install and run your
program, they can turn it back into source code. Granted, this
won't necessarily be the same source that you started with, but
it will be some kind of source code. The real way to keep your secret
algorithm a secret is, alas, to apply the proper number of attorneys;
they can write a license that says "you can do
<em class="emphasis">this</em> with the code, but you can't do
<em class="emphasis">that</em>. And if you break our rules, we've
got the proper number of attorneys to ensure that you'll regret
it."
</p>

<p>If you think you really want to compile your Perl code to make a
binary, though, see <a href="ch01_04.htm#lperl3-CHP-1-SECT-4.3">Section 1.4.3, "But How Do I Compile Perl?"</a> later in this
chapter.
</p>

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