Insert a variable without quotes

LaneM1234 has asked for the wisdom of the Perl Monks concerning the following question:

I have a code that looks through an HTML file and grabs the code between a day, (in the code, 4/23/012), and the end of that table column. The code works when I input the day manually, but if I try to make it a variable (i.e. $date), the code breaks down. If I add quotes to the day in the code, it breaks as well. I am assuming the code breaks down because of the quotes, which must be added in when I try and use a variable. Please help! I'm so close!

use strict;
use LWP::Simple;
print "What day?";
my $date = <>;
my $url = 'http://staweb.sta.cathedral.org/departments/math/mhansen/pu
+blic_html/1112hcal/1112hcal.htm'|| die "Specify URL on the cmd line";
my $html = get ($url);
$html =~ m{4/23/012(.*?)<td width="3%" style='width:3.12%;border:none;
+padding:0in 5.4pt 0in 5.4pt'>}gism;
print "$1\n";

use Fcntl; #The Module

print "content-type: text/html \n\n"; #The header
sysopen (HTML, 'myhtml.html', O_RDWR|O_EXCL|O_CREAT, 0755);
printf HTML "$1\n"; 

close (HTML);
[download]

Comment on Insert a variable without quotes Download Code

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Re: Insert a variable without quotes by Eliya (Vicar) on Jun 21, 2012 at 20:48 UTC
`my $date = <>;` [download] You don't show how you actually tried to use the value, but I suspect the problem is that you don't chomp `$date`, so it still contains the newline...	[reply] [d/l] [select]
Re: Insert a variable without quotes by davido (Cardinal) on Jun 21, 2012 at 21:59 UTC
`chomp $date; $html =~ m{\Q$date\E(.*?)..............}ism;` [download] Key components: chomp, quotemeta (or the `\Q` and `\E` metacharacters, and omitting the `/g` modifier, which isn't doing anything for you here (you're only matching once, and not in list context anyway). Also, you're working to hard at printing your output file. `open my $HTML, '>', 'myhtml.html' or die $!; print $HTML "$1\n"; close $HTML or die $!;` [download] I don't think your content-type line is doing anything for you here unless you're creating a CGI script, in which case you probably wouldn't be opening an output file, but instead would just be printing to STDOUT (the default). Dave	[reply] [d/l] [select]
Re: Insert a variable without quotes by ww (Archbishop) on Jun 21, 2012 at 21:16 UTC
`chomp` your input. The trailing newline is giving you the problems you're attributing to quotes. Line 7 probably takes a much bigger bite than you need. The td and style attributes have nothing to do with your assignment. But, OTOH, you might like to say: `$html =~ m{$date(.?)(?=</tr>)}gms;` to make sure you get the whole mess. Did /me just call that assignment page a mess?* Yep! It appears that the maker is using MS Word (or possibly, some other M$, gefuksperated generator of HTML) producing excessively verbose, unnecessarily obscure code. You have my sympathy, because the best you'll get directly from this site is something like this: 977707.pl What day? 4/24/012 Wide character in print at D:\_Perl_\pl_test\977707.pl line 14, <> lin +e 1. <o:p></o:p></span></p> </td> <td width="85%" valign=top style='width:85.66%;border:none;backgroun +d:white; padding:.75pt .75pt .75pt .75pt'> <p class=MsoNormal style='tab-stops:decimal .5in left 109.85pt'><b style='mso-bidi-font-weight:normal'><span style='font-size:10.0pt'>A +P Exam-<span class=SpellE>ish</span> Test, Part IA (multiple <span class=GramE>ch +oice</span>, no calculator).</span></b><span style='font-size:10.0pt'> We will st +art at 7:55 sharp: 28 questions in 55 minutes.<br> <br> HW due (will not be collected until next week): another 70 minutes&# +915;اض worth of AP review problems, double dose over the long weekend.<o:p></o:p></s +pan></p> </td> <td width="3%" style='width:3.12%;border:none;padding:0in 5.4pt 0in +5.4pt'> <p class=MsoNormal><span style='font-size:10.0pt'><o:p> </o:p>< +/span></p> </td> [download] Dealing with the encoding that produces the initial "wide character" report would be trivial, but getting rid of the proprietary tags and css will be a major PITA. FTR, the following code produced the above output but it still has problems -- such as the omission of a line to IMMEDIATELY assign the value in $1 to a named $var and the uninformative and misleading message in your `or die`: `#!/usr/bin/perl use 5.014; use LWP::Simple; print "What day? "; my $date = <>; chomp $date; my $url = 'http://staweb.sta.cathedral.org/departments/math/mhansen/pu +blic_html/1112hcal/1112hcal.htm'\|\| die "Specify URL in the form 'm/dd +/0yy'"; my $html = get ($url); $html =~ m{$date(.*?)(?=</tr>)}gms; print "$1 \n";` [download] And BTW, this smells even more like homework, now, given the assignment date is nearly 2 months past.	[reply] [d/l] [select]
Re: Insert a variable without quotes by frozenwithjoy (Priest) on Jun 21, 2012 at 20:36 UTC
Can you please elaborate on what you mean by "the code breaks down"? Maybe show the output when it works and when it doesn't.	[reply]