2012-02-03

I switch between Gedit, Notepad++, and vim fairly often depending on what I'm doing and whose computer I'm on. Sometimes I end up with tab characters where I really wanted four spaces, mainly when I'm using vim and I haven't figured out how to get vim to not do this. Gedit and Notepad++ have settings to use spaces instead of tabs, so there's no issue there.

Either I don't notice the tab characters until after I've put lots of them in the file I'm editing, or I'm editing a file from someone else whose editor uses tab characters for indentation. I know its not a big deal to some people, but tab indentation mixed with space indentation is a huge pet peeve of mine.

Thus, a perl script was born:

#!/usr/bin/perl -w

use File::Copy;

# This script replaces tab characters in a file with four spaces, or whatever else you want

$num_args = $#ARGV + 1;
$num_warnings = 0;
$tab_replace = "    ";  # Change this to whatever you want in place of tabs

if ( $num_args == 0 ) {
    print "usage: strip-tabs.pl file1 [file2, file3...]\n";
    exit;
}

# Have files to parse...
for my $f ( 0 .. ($num_args - 1) ) {
    if ( open(INPUTFILE, "<$ARGV[$f]") ) {
       if ( open(OUTPUTFILE, ">$ARGV[$f]~") ) {
           # Start parsing the file
           while ( my $line = <INPUTFILE> ) {
               $line =~ s/\t/$tab_replace/g;
               print OUTPUTFILE $line;
           }
           # Copy over original file here
           close(OUTPUTFILE);
           close(INPUTFILE);
           if ( !move("$ARGV[$f]~", $ARGV[$f]) ) {
               print "Could not write output to file $ARGV[$f]: $!\n";
               $num_warnings += 1;
           }
       }
       else {
           close(INPUTFILE);
           print "Could not create output file for $ARGV[$f]: $!\n";
           $num_warnings += 1;
       }
    }
    else {
        print "Could not open $ARGV[$f] for reading: $!\n";
        $num_warnings += 1;
    }
}
die "$num_warnings warnings encountered during file operation." unless $num_warnings == 0;

View Gist (strip-tabs.pl)

Feel free to gank away if you find it useful!

2012-02-03

Strip tab characters from multiple text files and replace them with spaces (or something else)