in reply to Re: Cleaning up Code
in thread Cleaning up Code

First I would like to thank you, Grandfather, and Mike Lieman for such quick replies. 
What fetchrow_array returns in scalar context is undocumented.
$data1 = $sth->fetchrow_array();
is wrong. If you want to the first field, use
($data1) = $sth->fetchrow_array();

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Thank you I will take your advice here. 
Is the contents of $dberror text of HTML? You put both into it. At wor
+st, this could be an opening for a cross-site scripting attack.

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I do ultimately call $dberror in my html code yes. I do not understand what you mean by stating I put both into it? Again please forgive me this is my first attempt at coding anything. 
All over, you are instructing Perl to ignore prototypes. Why do you us
+e & on your subroutine calls?

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I was under the impression that this was proper usage... All the examples I discovered on the web used the & before the subroutine. 
I note a distinct lack of my. Use use strict;!

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Again please forgive my inexperience here... I did a fast google search to find the benefit in using "my()".. am I correct in stating the primary reason in using "my()" is so that the variables are completely hidden from the outside? 
Something tells me you don't use warnings either. ("if ($data1 ne $dig
+est1)" would warn if fetchrow_array returned zero rows.) Use use warn
+ings;!

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I actually want it to return with zero rows, I do plan on adding DBI error codes for my prepare and execute commands. 
Why is six in quotes in "if (scalar @row1 == "6")"? You want to compar
+e with the number 6, not the string "6" (which would be converted to 
+a number by ==). The scalar is useless too. == creates a scalar conte
+xt, so scalar is redundant.

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My goal with this statement is to see if my @row1 has 6 elements, and if it does proceed on. So if I read what you stated, I could accomplish the same thing by doing this 
if (@row1 == 6) {
     other code here ...
};

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?? 
for my $row ( 1 .. $#rows ) {
   if (@{ $rows[$row] } == "6") {
      my @entry = (@required , @row);
      ...
   }
}

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Thank you for this! In trying to understand how this statement works, could I trouble you once more to explain how this exactly works? Again Thank you for you help thus far!!

Mike, Thank you for your input, and I have tested this to the best of my ability so I believe my script is at a good point for "cleaning up". Hopefully I am not being ignorant, are their other ways to test my script other than using my program, and getting the results I hope for? I do try to "break" it by putting in invalid data, etc.

Grandfather, @row1 is an array that is put together earlier after parsing data from a html form. So the scalar line is to look to see if it has all the required elements before it proceeds on with the script. Ideally there should only be 6 or 0 elements in the array, but to be thorough, and sure that information is being entered correctly and completely I wanted to be sure there were 6 elements in the array. Hopefully that's clearer than mud...

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Re^3: Cleaning up Code
by ikegami (Patriarch) on Dec 10, 2008 at 03:37 UTC

    I do not understand what you mean by stating I put both into it?

    @entry1 contains text and not HTML, right? At the very least, it needs to visit HTML::Entities.

    I was under the impression that this was proper usage

    It disables prototypes and allows subroutines to be called without parens before they are declared. It was possibly the way to do things in Perl4, but this isn't Perl4.

    the primary reason in using "my()" is so that the variables are completely hidden from the outside?

    Yes. It limits the scope of the variables. This prevents accidental clobbering of the variables by distant code and it fosters modularity of code. In conjunction with use strict;, typos in variable names are usually caught at compile-time. use strict; helps identify a couple of other type of dangerous code. 

       my @entry = (@required , @{$rows[$row]});
   my $digest = sha1_hex(@entry);
   my $sth = $dbh->prepare($query);
   $sth->execute($digest);
   my ($data) = $sth->fetchrow_array();
   ...

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    I actually want it to return with zero rows

    Yes, but you don't want it to warn "Use of uninitialized value in string eq" when it does. defined would be one way of avoiding the warning.

    So if I read what you stated, I could accomplish the same thing by doing this

    Yes. @row1 == 6 checks if @row has 6 elements. An array in scalar context (as imposed by scalar but also by ==) evaluates to the number of elements in the array.

    In trying to understand how this statement works

    All variables other than @row1 can lose the "1" without problem. The rows are a little bit trickier since we want to switch to using a loop. Unfortunately, you haven't shown us everywhere @rowX is used — in particular, you haven't shown us where they're created — so our help there is limited.

    Basically, I suggested that you create an array @rows whose elements are references to arrays (formerly @row1, @row2, etc). This is commonly called an "array of arrays". Basically, Perl's version of a two-dimensional array. There's perllol on the subject, for starters.

    Note: I've updated my post to fix a bug in that code.

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      Thank you again for your response. I was hoping I could provide this snippet and take what I learn from it and clean up my entire script. However, it appears as if I may need to show you my entire script to ensure I don't shoot myself in the foot later. I appreciate the time you've already spent on this with me but would you be willing, if I show you my entire script, to provide me with some guidance/suggestions to get my script cleaned up?
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        Sure, I can have a look at it.
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