Re^2: to avoid redundacy in a file

To avoid redundancy in your code, you could do this:

my %seen;

while (<>)
{
     next if ($seen{$_}++);
     print;
}
[download]

You can do it in one shot, so you might as well. Note that this code eliminates all duplicate lines, not just repeated ones. If you want to just ditch repeats, use this:

my $last;

while (<>)
{
     next if ($_ eq $last);
     $last = $_;
     print;
}
[download]

Thus lines "A A A B B B A A C C" will be "A B A C" not "A B C" as in the previous bit.

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Re^3: to avoid redundacy in a file by Aristotle (Chancellor) on Jul 15, 2002 at 13:55 UTC
You can do it in one shot, so you might as well. That makes your second snippet `my $prev; while (<>) { next if ($_ eq $prev); print $prev = $_; }` [download] `:^)` Wait, we can shorten that.. `my $prev; while (<>) { print $prev = $_ unless $_ eq $prev; }` [download] Hmm.. `my $prev; $_ ne $prev and print $prev = $_ while <>;` [download] Err.. sorry, got carried away for a second.. Perl is just too seductive. Sigh. `:-)` Makeshifts last the longest.	[reply] [d/l] [select]
Re^4: to avoid redundacy in a file by tadman (Prior) on Jul 15, 2002 at 19:06 UTC
I was going to condense it down to a single line: `% perl -ne '$p ne$_&&print;$p=$_' ...`	[reply] [d/l]