perl scriptlet to expand tabs into blanks
 2019 by C. Masloch

Usage of the works is permitted provided that this
instrument is retained with the works, so that any entity
that uses the works is notified of this instrument.

DISCLAIMER: THE WORKS ARE WITHOUT WARRANTY.

12387  [2019-08-23 23:05:04 +0200 Aug Fri] cp -a test.txt test.cvt && perl -i -e 'our $tabstopwidth = 8; our $replacebool; sub replacefunc { my ($length) = @_; our ($tabstopwidth, $replacebool); s/^((:?[^\t]{$tabstopwidth})*[^\t]{$length})\t/$replacebool = 1; $1." " x ($tabstopwidth - $length)/e; }; while (<>) { do { $replacebool = 0; foreach my $length (0 .. $tabstopwidth - 1) { replacefunc($length); }; } while ($replacebool); } continue { print or die "-p destination: $!\n"; }' test.cvt && od -Ax -tx1z test.cvt; cat test.cvt
12388  [2019-08-23 23:06:40 +0200 Aug Fri] history 4 >> ~/wwwecm/perl-expand-tabs.txt
12389  [2019-08-23 23:12:07 +0200 Aug Fri] cp -a test.txt test.cvt && perl -i -e 'our $tabstopwidth = 8; our $replacebool; sub replacefunc { my ($length) = @_; our ($tabstopwidth, $replacebool); s/^((:?[^\t]{$tabstopwidth})*[^\t]{$length})\t/$replacebool = 1; $1." " x ($tabstopwidth - $length)/e; }; while (<>) { do { $replacebool = 0; foreach my $length (0 .. $tabstopwidth - 1) { replacefunc($length); }; } while (/\t/); } continue { print or die "-p destination: $!\n"; }' test.cvt && od -Ax -tx1z test.cvt; cat test.cvt
12390  [2019-08-23 23:12:33 +0200 Aug Fri] history 4 > ~/wwwecm/perl-expand-tabs.txt