Can I modify scalars contained in the array ref returned by DBI

[Aaron Anodide]

Hi,

I'm fairly new to PERL. The following code fetches a row from DBI as
an array ref. It then sends a reference to an element of that array
to a sub which modifies it in place. This effectively (i think)
modifies the original string which was returned by DBI.

My question is: Is this OK? Are the scalars in the array returned
from DBI special in any way, such that I might corrupt memory by doing
this?

Thanks in advance,
Aaron Anodide

sub CleanXMLString
{
my $s_ref = shift;
$$s_ref =~ s/\&/\&amp\;/g;
$$s_ref =~ s/\</\&lt\;/g;
$$s_ref =~ s/\>/\&gt\;/g;
}

my $sql = "SELECT x,y FROM TT WHERE ID=1";

$sth = $dbh->prepare($sql);

$sth->execute();

$row_ref = $aref = $sth->fetchrow_arrayref;

CleanXMLString( \$row_ref->[0] );
CleanXMLString( \$row_ref->[1] );

 

[gnari]

Hi,

I'm fairly new to PERL. The following code fetches a row from DBI as
an array ref. It then sends a reference to an element of that array
to a sub which modifies it in place. This effectively (i think)
modifies the original string which was returned by DBI.

My question is: Is this OK? Are the scalars in the array returned
from DBI special in any way, such that I might corrupt memory by doing
this?

yes, in the case of DBI, it is OK.

gnari

 

[Eric Amick]

sub CleanXMLString
{
my $s_ref = shift;
$$s_ref =~ s/\&/\&amp\;/g;
$$s_ref =~ s/\</\&lt\;/g;
$$s_ref =~ s/\>/\&gt\;/g;
}

The backslashes really aren't necessary.

 

[John Bokma]

The backslashes really aren't necessary.

Also the > doesn't need to be escaped in many cases.
<something> a > b </something> is valid.

 

[Aaron Anodide]

yes, in the case of DBI, it is OK.

Thank you for your response.

Regards,
Aaron

 

[Aaron Anodide]

The backslashes really aren't necessary.

Thanks for that. It made my code cleaner.

Regards,
Aaron

 

[Aaron Anodide]

Also the > doesn't need to be escaped in many cases.
<something> a > b </something> is valid.

That's interesting, I didn't know it. I wonder if it's worth the
effort to analyze the context of the >'s though...

Regards,
Aaron

 

[John Bokma]

(e-mail address removed) (Aaron Anodide) wrote in

That's interesting, I didn't know it. I wonder if it's worth the
effort to analyze the context of the >'s though...

I import (Perl) code into XML, and only escape the < and &. There probably
is a module which has a nice escape function for this. (And I guess it
escapes the > too).

 

[Brad Baxter]

That's interesting, I didn't know it. I wonder if it's worth the
effort to analyze the context of the >'s though...

http://www.w3.org/TR/REC-xml/#syntax

Regards,

Brad

 

[Aaron Anodide]

http://www.w3.org/TR/REC-xml/#syntax

Regards,

Brad

Thanks! So if I read this right, I still have to search my whole
document for >'s because of the rare case that it is in the string ]]>
and it's not a CDATA section.

Aaron