Making multiple replaces through Regex

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

In a file, I want to insert an element that number of times which is specified in the attribute. Value specified in <csp c="(\d+)"> will be taken and replaced with <colspec colnum="1" colname="col1"/>.

The program line for that is:

$_ =~ s/<csp c="(\d+)">/"<colspec colnum=\"1\" colname=\"col1\"\/>" x $1/egs;

This is working fine, but I need the number mentioned in colnum and colname needs to be incremented by one everytime. If I use a variable and increase it by one with the following code, I am not getting the numbers.

$_ =~ s/<csp c="(\d+)">/"<colspec colnum=\"$num\" colname=\"col$num++\"\/>" x $1/egs;

To be more precise, if the input is <csp c="3">, the output should be:

<colspec colnum="1" colname="col1"/>
<colspec colnum="2" colname="col2"/>
<colspec colnum="3" colname="col3"/>
[download]

Could anyone help me please?

Comment on Making multiple replaces through Regex Select or Download Code

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Re: Making multiple replaces through Regex by sathiya.sw (Monk) on Nov 27, 2008 at 06:46 UTC
If iterations are ok for you, then try the following.. `if(/<csp c="(\d+)">/) { $number= 1; $iteration = $1; $string .= '<colspec colnum="'. $number . '" colname="col' . $number+ ++ . '"/>' while ( $iteration-- ); } print $string;` [download] code is, first check whether format given is right, if it is then use some temporary variables, and do the string concatenation with the help of it.	[reply] [d/l]
Re: Making multiple replaces through Regex by prasadbabu (Prior) on Nov 27, 2008 at 06:15 UTC
Hi rsriram, It is working fine for me. If I am wrong somewhere, please correct me. Below is a sample code. `$s = '<csp c="3">'; $s =~ s/<csp c="(\d+)">/"<colspec colnum=\"1\" colname=\"col1\"\/>\n" +x $1/egs; print $s; output: -------- <colspec colnum="1" colname="col1"/> <colspec colnum="1" colname="col1"/> <colspec colnum="1" colname="col1"/>` [download] Prasad	[reply] [d/l]
Re^2: Making multiple replaces through Regex by rsriram (Hermit) on Nov 27, 2008 at 06:18 UTC
Hi Prasad, Upto this its working for me too! But my desired output is `<colspec colnum="1" colname="col1"/> <colspec colnum="2" colname="col2"/> <colspec colnum="3" colname="col3"/>` [download] The value in `colnum` and `colname` needs to get incremented everytime! Thanks.	[reply] [d/l] [select]
Re: Making multiple replaces through Regex by parv (Parson) on Nov 27, 2008 at 06:55 UTC
`$_ =~ s/<csp c="(\d+)">/"<colspec colnum=\"1\" colname=\"col1\"\/>" +x $1/egs;` [download] Note that `qq//` can be substituted for `""` for the same effect. That way there will no need to escape a `"`. Similarly, `/` delimiter can be substituted with other character(s) which do(es) not appear in your pattern or replacement to avoid escaping of the delimiter character ... `$_ =~ s[<csp c="(\d+)">][qq(<colspec colnum="1" colname="col1"/>) x $1 +]egsx;` [download]	[reply] [d/l] [select]
Re: Making multiple replaces through Regex by jwkrahn (Abbot) on Nov 27, 2008 at 07:06 UTC
`$ perl -le' $_ = q[ <csp c="3"> ]; print; s{<csp c="(\d+)">}{ join "", map qq[<colspec colnum="$_" colname="col$ +_"/>], 1 .. $1 }eg; print; ' <csp c="3"> <colspec colnum="1" colname="col1"/><colspec colnum="2" colname="col2 +"/><colspec colnum="3" colname="col3"/>` [download]	[reply] [d/l]
Re: Making multiple replaces through Regex by Punitha (Priest) on Nov 27, 2008 at 06:23 UTC
Try like this, `my ($colno) = $_ =~ /<csp c="(\d+)">/; my $csp; for my $i (1..$colno) { $csp = $csp."<colspec colnum=\"$i\" colname=\"col$i\"\/>\n"; } $_=~s/<csp c=\"$colno\">/$csp/g; print "$_";` [download] Punitha	[reply] [d/l]