CODEWITHSUNDEEP
stringperlconcatenation
avs3323
avs3323

Reputation: 77

Perl string concatenation overlaying strings

I am trying to concatenate 3 strings in perl, and I am getting weird behavior. The data was just written to a file previously in the script, and I am trying to add two columns to the data.

Here is my code and its behavior

print "phylipId is $phylipId\n";
print "Tree is $tree\n";
print "Line is $line\n";

my $string = join "\t", $phylipId, $tree, $line;

print "Concatenated is $string\n";

Gives me this output

phylipId is 4
Tree is (138,((139,141),140));
Line is 000931  17.0    1.0 0.135   no  1044    646918204
Concaten000931s 17.0    1.08,((10.1351),no0));  1044    646918204

This also happened when I used the . operator. Any help would be appreciated

Upvotes: 2

Views: 1315

Answers (3)

Borodin
Borodin

Reputation: 126722

As patrick says, it is more than likely you have read a DOS-formatted file on a Linux box. In those circumstances, if you use chomp on a string terminated with "\r\n" you will be left with the "\r".

The simplest way to clean up records like this is to replace chomp with

s/\s+$//

which, since both "\r" and "\n" count as whitespace, will remove both from the string simultaneously. If trailing tabs and spaces are important for you then use

s/[\r\n]+$//

instead, or perhaps

s/[[:cntrl:]]+$//

or

s/\p{Control}+$//

Upvotes: 1

phemmer
phemmer

Reputation: 8807

It looks like youre reading $tree from a file using carriage-returns (\r), and $tree is ending up with \r at the end of it causing it to seek to the beginning of the line.

See this test:

perl -e 'print("abcdefghijkl\r\t012\n");'

Which outputs

abcdefgh012l

Upvotes: 4

Renaud Bompuis
Renaud Bompuis

Reputation: 16786

I'm not able to replicate your issue after trying under Windows and Linux.

  • Could the issue be related to how your console is configured?
  • does it happen on other machines too?
  • Can you tell more about your exact environment?
  • What happens if you try to print that line to a text file instead of stdout?

Upvotes: 0

Related Questions