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Redundant code

Zeke_D
Deleted

Jul 2, 2000, 5:54 PM

Post #1 of 4 (701 views)

Redundant code	Can't Post

Hello!

the following code should take a QUERY STRING and seperate it by the '&' seperators...

@DATA = split(/&/,$ENV{'QUERY_STRING'});
foreach (@DATA) {
($variable1, $variable2) = split(/&/,$ENV{'QUERY_STRING'});
}

So if you ran foo.pl?fo&fum this string would
basically do this:
$variable1 = "fo";
$variable2 = "fun";

It works just fine, just looks redundant. multiple 'split's anyone think of a streamlined way to do this?

japhy
Enthusiast

Jul 2, 2000, 7:00 PM

Post #2 of 4 (701 views)

Re: Redundant code [In reply to]	Can't Post

I think you have your idea wrong. Your code is quite redundant. The QUERY_STRING is sent in the form FIELD=VALUE&FIELD=VALUE&... If there is nothing between the = and the &, the value is "". If there is a & immediately after the FIELD, assume a true value (1).

So your code should really be:

<BLOCKQUOTE>code:<HR>

@DATA = split /&/, $ENV{QUERY_STRING};
for (@DATA) {
push @FIELDS, (s/([^=]+)//, $1)[1]; # the non = characters
push @VALUES, (s/^=// ? $_ : 1);
}
</pre><HR></BLOCKQUOTE>

If the QUERY_STRING is 'foo=bar&this=&that', then @FIELDS = ('foo','this','that'), and @VALUES = ('bar','',1).

Then again, perhaps CGI.pm is right for you.

<BLOCKQUOTE>code:<HR>

use CGI;
$query = new CGI;
$value_of_foo = $query->param('foo');
</pre><HR></BLOCKQUOTE>

Note: CGI.pm's query parsing dictates that a field with no =VALUE associated with it has a value of undef, whereas a field with an =, but no VALUE, as a value of "".

Kanji
User

Jul 2, 2000, 7:32 PM

Post #3 of 4 (701 views)

Re: Redundant code [In reply to]	Can't Post

<BLOCKQUOTE>code:<HR>

($variable1, $variable2) = split(/&/,$ENV{'QUERY_STRING'});</pre><HR></BLOCKQUOTE>
... should suffice, as what you're doing is resetting the two variables after already setting them. ie,

<BLOCKQUOTE>code:<HR>

foreach( @DATA ) { ... }
# is the same as
foreach ( "fo", "fum" ) { ... }
# is (functionally) the same as
foreach ( 1, 2 ) { ... }
# is the same as
...
...</pre><HR></BLOCKQUOTE>

For scalability, tho', I'd stick with the array assignment because you could then access variables as $DATA[0] (fo), $array[1] (fum), etc. but not have to hardcode any more variables if you decided to pass more arguments.

It's odd to see arguments like that passed to a script though. Usually they take a key/value form like ?colour=blue&indent=yes.

I suspect that's where you got your redundant loop from as there's lots of code out there like ...

<BLOCKQUOTE>code:<HR>

@pairs = split(/&/,$ENV{'QUERY_STRING'});
foreach $pair (@pair) {
($key,$value) = split(/=/,$pair);
$inpput{$key} = $value;
}</pre><HR></BLOCKQUOTE>

(Note the second split on = not &).

However, is this is what you were really after, I'd advise you to use CGI.pm or one of the other CGI modules instead. Makes life a lot easier and saves you reinventing the wheel.
If that's what you had in mind, then you should take

[This message has been edited by Kanji (edited 07-02-2000).]

Zeke_D
Deleted

Jul 2, 2000, 9:41 PM

Post #4 of 4 (701 views)

Re: Redundant code [In reply to]	Can't Post

Thanks Kanji,
Your condensing of my code is so simple, i should've figured it out, but you know how it is you code and code and the simplist strings escape you.
I probably wont use cgi.pm, as the variables only need to be declared once.
thanks again (the new code is already inserted to the program) If anyone cares, the script is located at http://www.yavapaiopen.com/cgi-bin/netrep.pl
and a text file of it at /cgi-bin/netrep.txt

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