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Trouble with Splitting in Perl
#1
Hi,

I've been going back to reading my notes on the Perl language back in college, and I, unbelievingly, have reached an impasse. It's just the this isn't quite the problem that I had last time. Let's get into it.

Here's the delimited file; the delimiter is the | character
Code:
Colombian|The finest Colombian beans, low flame roasted to yield a rich flavour.|7.99|The finest Colombian beans, low flame roasted to yield a rich flavour.In the cup, Colombian offers a rich mellow flavor, pleasant acidity and heady aroma. The flavor is consistent clean and balanced with a strong finish. Ideal as your everyday coffee, but particularly good as that morning eye opener.

Here's my code:
Code:
#!C:\strawberry\perl\bin\perl.exe
print "Content-type: text/html\n\n";

# Open the Coffee Descriptions file for output (coffee_info.txt)
open COFFEE, "<coffee_info.txt";

# Collect some information from the Coffee Descriptions and output it
while(<COFFEE>)    # While still able to collect info
{
    ($name, $short, $price, $long) = split(/|/,$_);
    print "<STRONG>$name</STRONG>: $short<BR>";
} # End collect info and output while

# Close the file
close COFFEE;

And here's the output, which isn't the intended output:
Code:
C: o

The ideal output that I can't manage was to print out the first two fields of each entry, so if you read the code, it would be like this per entry:
Code:
Colombian: The finest Colombian beans, low flame roasted to yield a rich flavour.

I'm not cheating by telling people to do my homework for me. I didn't know how I wasn't stuck on this the first time around, and I know should have paid some more attention. Like I said though, it didn't come around the first time.

Please, if you have a clue as to how I should be coding this, I would be interested in listening to it.

Thank you.

EDIT: Just so you know, I have been reading up on the split command, and it was no different from the notes I received in college. Maybe I should find a better e-book and not count on my prof's notes.
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#2
Try:
($name, $short, $price, $long) = split /\|/;
('|' would be interpreted as logical OR and has to be escaped). Have also removed $_ as it would be default if not provided.

Also remember to add a 'die' to the open call.
open COFFEE, "<coffee.txt" or die "Unable to open input file:$!\n";

Hope it works now.

perldoc -f split
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#3
http://www.comp.leeds.ac.uk/Perl/split.html

Why Pearl anyway?
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#4
No particular reason, I was trying to revise my notes from college.

Why? What is it with Perl?

EDIT: This just in! The correction works! Thank you SectorVector. So let me get this straight: if I didn't use escapes, the | character would be mistaken as a logical OR, just as a & character would be an and, right?
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#5
Yay!
Um. Yes and No. '&' is fine as it is. The first argument to split is a pattern. So '|' alone has special meaning.
You can't associate a semantic to '&' in a pattern. So it would be the literal '&'.

So, ($a,$b) = split /&/, "Hello&World";

would assign Hello to $a and World to $b

- man perlre should help with patterns.
- Mastering regular expression by Jeffrey Friedl is a good and complete reference book.

Programming Perl (3 authors) and Perl Cookbook by Tom C are more than enough.
Learning Perl by Randall Schwartz is a good beginners book too.

PS:I love perl bcos it is "idiomatic" and great for small/medium sized "tasks". TMTOWTDI.
Reply
#6
The purpose of what I'm doing is to review my college stuff, but thanks.

No more questions. Smile
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