Perl code to format the text file by inserting tag in blank line

DAN0207 has asked for the wisdom of the Perl Monks concerning the following question:

I have a input file with contents as below:

<mt>llbreserve_Stov1</mt>
      <mt>llbreserve_Stov2</mt>
      <mt>preserve_Stov1</mt>
      <mt>qreserve_Stov1</mt>
      <mt>qreserve_Stov2</mt>
      <mt>mnreserve_Stov1</mt>
      <mt>slmreserve_Stov1</mt>
      <mt>slmreserve_Stov2</mt>
      <mt>envreserve_Stov1</mt>
      <mt>envreserve_Stov2</mt>
      
      <mv>
<value>MT=DUOSQ2,Eb=43789,Fc=67890</value>
        <r>0</r>
        <r>0</r>
        <r>0</r>
        <r>0</r>
        <r>0</r>
        <r>0</r>
        <r>0</r>
        <r>0</r>
        <r>0</r>
        <r>0</r>
        </mv>
[download]

I have written the code(pasting here only the specific code,not all lines)as below:

# Writing output from mt step until mv for reserve meas only
                    $dimens=scalar(keys(%ind));
                    for ($jj=1; $jj <= $dimens; $jj++)
                    {
                        # Writing output mt reserve meas list
                        print OUTFILE "<mt>$kpi[$jj]<\/mt>\n";
                    }
                    foreach $value (keys %result)
                    {
                        foreach $ext (keys %{$result{$value}})
                        {
                            print OUTFILE "<mv>\n";
                            print OUTFILE "$value".",resv="."$ext<\/va
+lue>\n";
                            for ($jk=1; $jk <= $dimens; $jk++)
                            {
                                # Writing output r meas list result so
+rted in the same order than mt list
                                print OUTFILE "$result{$value}{$ext}{$
+kpi[$jk]}\n";
                            }
                            print OUTFILE "<\/mv>\n";
                        }
                    }
                    print OUTFILE "$line\n";
[download]

The output file which i get after executing the code is

      <mt>llbreserve</mt>
      <mt>preserve</mt>
      <mt>qreserve</mt>
      <mt>mnreserve</mt>
      <mt>slmreserve</mt>
      <mt>envreserve</mt>
  <mv>
<value>MT=DUOSQ2,Eb=43789,Fc=67890,resv=Stov1</value>
        <r>0</r>
        <r>0</r>
        <r>0</r>
        <r>0</r>
        <r>0</r>
        <r>0</r>
</mv>
<mv>
<value>MT=DUOSQ2,Eb=43789,Fc=67890,resv=Stov2</value>
                <r>0</r>

        <r>0</r>
        
        <r>0</r>
        <r>0</r>
[download]

I can see that there are some blank lines where the combination is not present(Stov1 is present for all meas whereas Stov2 is not present for all.)I am planning to insert a tag like <r></r> in place of blank lines so that further processing of my outputfile is valid. Could you pl. help me to achieve this.TIA

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Re: Perl code to format the text file by inserting tag in blank line by GrandFather (Saint) on Feb 12, 2020 at 05:37 UTC
The sample data you give looks like a fragment of XML. If that is the case it is strongly advised that you use a suitable module (XML::Twig, XML::LibXML, ...) to do the heavy lifting for you. Optimising for fewest key strokes only makes sense transmitting to Pluto or beyond	[reply]
Re^2: Perl code to format the text file by inserting tag in blank line by DAN0207 (Acolyte) on Feb 12, 2020 at 05:47 UTC
Yes it is XML file format.and it is required to use only PERL code	[reply]
Re^3: Perl code to format the text file by inserting tag in blank line by GrandFather (Saint) on Feb 12, 2020 at 06:03 UTC
Yes, even you can use CPAN You may like to explain why you can't use cpan modules if that is indeed the case. Optimising for fewest key strokes only makes sense transmitting to Pluto or beyond	[reply]
Re^4: Perl code to format the text file by inserting tag in blank line by DAN0207 (Acolyte) on Feb 12, 2020 at 06:22 UTC
Re^5: Perl code to format the text file by inserting tag in blank line by afoken (Chancellor) on Feb 12, 2020 at 06:32 UTC
Re^5: Perl code to format the text file by inserting tag in blank line by AnomalousMonk (Archbishop) on Feb 12, 2020 at 06:44 UTC
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Re^3: Perl code to format the text file by inserting tag in blank line by AnomalousMonk (Archbishop) on Feb 12, 2020 at 05:57 UTC
By "it is required to use only PERL code", do you mean that you may not use Perl modules such as the ones suggested by GrandFather? Give a man a fish: `<%-{-{-{-<`	[reply] [d/l]
Re^3: Perl code to format the text file by inserting tag in blank line by Jenda (Abbot) on Feb 12, 2020 at 10:35 UTC
There's Perl (the language) and perl (the "interpreter"). There is no PERL. Jenda 1984 was supposed to be a warning, not a manual!	[reply]
Re: Perl code to format the text file by inserting tag in blank line by haukex (Archbishop) on Feb 12, 2020 at 10:27 UTC
You should definitely use an appropriate module for this - see Parsing HTML/XML with Regular Expressions for why. You said here that you have security restrictions, and I fully agree with afoken that not using the appropriate modules and instead reinventing the wheel makes it more likely that your code will be a security risk; you should speak to your managers about that. And you may already have the appropriate libraries installed anyway: XML::LibXML is based on `libxml2`, and XML::Parser (used in e.g. XML::Twig) is based on `libexpat`.	[reply] [d/l] [select]
Re: Perl code to format the text file by inserting tag in blank line by AnomalousMonk (Archbishop) on Feb 12, 2020 at 06:26 UTC
`$dimens=scalar(keys(%ind)); for ($jj=1; $jj <= $dimens; $jj++) { # Writing output mt reserve meas list print OUTFILE "<mt>$kpi[$jj]<\/mt>\n"; } ... ... for ($jk=1; $jk <= $dimens; $jk++) { # Writing output r meas list result sorted in the same ord +er than mt list print OUTFILE "$result{$value}{$ext}{$kpi[$jk]}\n"; } ... ... ...` [download] Just something that caught my eye... I don't know how you are initializing the `@kpi` array, but with this code, it needs one more element than the number of elements in the `%ind` hash (Perl arrays are 0-based by default). Give a man a fish: `<%-{-{-{-<`	[reply] [d/l] [select]
Re^2: Perl code to format the text file by inserting tag in blank line by Marshall (Canon) on Feb 13, 2020 at 02:01 UTC
I think the OP is probably ok here. He is using arrays in a "non-Perl" way and with explicit indices starting at 1 instead of 0. Not using `array[0]` is allowed. `$kpi[0]` is probably undef. "Off by one" is one of the most common errors in programming. I personally would rewrite the code so that it doesn't use indices at all like: `foreach my $element (@array){}` However a re-write like appears to be outside the scope of the question before us. Perl code like that would use index 0. However there would not be any direct reference to that zero index within the code at all. Creating the kpi array would use "push" instead of explicit indices from 1..n. If the OP creates the kpi array with starting with `$kpi[1]` that just makes index 0 undef (skips it). I don't see any indication that the OP is aware of: push,pop,shift,unshift.	[reply] [d/l] [select]
Re^3: Perl code to format the text file by inserting tag in blank line by AnomalousMonk (Archbishop) on Feb 13, 2020 at 06:00 UTC
I think the OP is probably ok here. I'm not so sure. DAN0207 is a self-described Perl "beginner", and looking at other posts by this monk doesn't give me the sense that he or she is necessarily aware of the issue of 0- versus 1-based arrays. We also cannot see anything about how the `@kpi` array is initialized. The whole thing made my buggy-sense tingle. However, DAN0207 hasn't seen the need to follow up on the point I made here (indeed, replying with a question on a completely different topic), so I guess everything's ok... Give a man a fish: `<%-{-{-{-<`	[reply] [d/l] [select]
Re^4: Perl code to format the text file by inserting tag in blank line by Marshall (Canon) on Feb 13, 2020 at 06:33 UTC
Re^2: Perl code to format the text file by inserting tag in blank line by DAN0207 (Acolyte) on Feb 12, 2020 at 08:05 UTC
I tried a perl one liner sepertaely on the output xml file as below: `perl -i -lpe "s/^\s$/<r><\/r>/g" test(filename i used to check separa +tely)` [download] But when i write this one liner in the main code as below, its not giving any output..(No xml output file is getting generated) `print OUTFILE "$result{$moid}{$ext}{$kpi[$jk]}\n"; perl -i -lpe "s/^\s$/<r><\/r>/g" $OUTFILE` [download] Could you pl. help on this.	[reply] [d/l] [select]
Re^3: Perl code to format the text file by inserting tag in blank line by AnomalousMonk (Archbishop) on Feb 12, 2020 at 08:30 UTC
`print OUTFILE "$result{$moid}{$ext}{$kpi[$jk]}\n"; perl -i -lpe "s/^\s$/<r><\/r>/g" $OUTFILE` [download] Command-line syntax cannot be included directly in Perl code. I'm surprised this would even compile! Be that as it may, you seem to be trying to check if the string `"$result{$moid}{$ext}{$kpi[$jk]}\n"` is a blank line and output `"<r></r>\n"` if it is. Try (untested): `my $out = "$result{$moid}{$ext}{$kpi[$jk]}\n"; $out =~ s{ \A \s \z }{<r></r>\n}xms; print OUTFILE $out;` [download] instead. Give a man a fish: `<%-{-{-{-<`	[reply] [d/l] [select]
Re^4: Perl code to format the text file by inserting tag in blank line by DAN0207 (Acolyte) on Feb 12, 2020 at 09:55 UTC
Re^5: Perl code to format the text file by inserting tag in blank line by AnomalousMonk (Archbishop) on Feb 12, 2020 at 22:26 UTC
Re^5: Perl code to format the text file by inserting tag in blank line by GrandFather (Saint) on Feb 12, 2020 at 10:18 UTC
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