Perl allows to use arithmetics on string
Here's the code:
#!/usr/local/bin/perl -w
use strict;
sub step_over_desert # () I won't repeat this mistake anymore!!!
{
print "Tsock...\n";
}
sub cover_the_distance # () I won't repeat this mistake anymore!!!
{
my ($me, $desert_width, $max_spit_distance, $num_legs, $last_name,
+ $day_phone, $days_without_water) = @_;
my $num_steps=0;
while($desert_width)
{
my $todo = $desert_width * $num_legs;
print "$desert_width miles remaining; $todo steps yet to do.\n"
+;
step_over_desert();
$desert_width--;
$num_steps += $num_legs;
}
print "Steps made: $num_steps\n";
}
#cover_the_distance("strong animal", 5, 15, 4, "Mabooka", "(123)-456-7
+890", -1);
cover_the_distance("strong animal", "five thousand miles", 15, 4, "Mab
+ooka", "(123)-456-7890", -1);
1;
Don't try it at home
Well, I recommend at the very least to redirect the output to a file:-).
Why people do this?
Again, the main reason: because it allows you. One may expect either a compile-time error or a run-time exception. But Perl allows you to shoot your own foot.
Actually, this is an obfuscated (starting to love the word) code from a real-life app. The real application would send a query over the wire to the server,
get a responce line --
-- that should look smth. like this:
200 OK 578
-- meaning " there're 578 lines yet to read from the socket,
parse this line and create a loop:
while($numlines) {
get_next_one(...);
$numlines--;
...
}
Well guess what? Once in 10000 times the server would get tired and send a garbled status line -- smth. like:
200 OK whatever,man
and
(while "whatever,man"--)
{....}
will start the almost infinite loop. (Try the code above).
Solution
Be aware.
use int($n).
Ask your new hires during the inteview: "What is the result of the following operation:
"Larry"--;
-?.
-
Are you posting in the right place? Check out Where do I post X? to know for sure.
-
Posts may use any of the Perl Monks Approved HTML tags. Currently these include the following:
<code> <a> <b> <big>
<blockquote> <br /> <dd>
<dl> <dt> <em> <font>
<h1> <h2> <h3> <h4>
<h5> <h6> <hr /> <i>
<li> <nbsp> <ol> <p>
<small> <strike> <strong>
<sub> <sup> <table>
<td> <th> <tr> <tt>
<u> <ul>
-
Snippets of code should be wrapped in
<code> tags not
<pre> tags. In fact, <pre>
tags should generally be avoided. If they must
be used, extreme care should be
taken to ensure that their contents do not
have long lines (<70 chars), in order to prevent
horizontal scrolling (and possible janitor
intervention).
-
Want more info? How to link
or How to display code and escape characters
are good places to start.