Hello,
Converting from Perl to Ruby, I am trying to find an equivalent to this
Perl one-liner removing duplicate lines in a file (without sorting it at
first) :
perl -ne'$s{$_}++||print' infile >outfile
I guess uniq method could be used, but I can't find how.
Many thanks in advance,
--
Damien Wyart
I tried creating a version that mimics the Perl one (because Ruby also
has the -n option), but in the end this seemed easier (and much more
readable):
ruby -e "puts IO.readlines(ARGV[0]).uniq" infile > outfile
So you are right about using uniq.
Ryan
On 10/5/05, Damien Wyart <damien.wyart@free.fr> wrote:
Hello,
Converting from Perl to Ruby, I am trying to find an equivalent to this
Perl one-liner removing duplicate lines in a file (without sorting it at
first) :perl -ne'$s{$_}++||print' infile >outfile
I guess uniq method could be used, but I can't find how.
Here is a pretty close translation that does what you want:
ruby -ne 's||={};s[$_]||print;s[$_]=true'
--- Damien Wyart <damien.wyart@free.fr> wrote:
Hello,
Converting from Perl to Ruby, I am trying to find an
equivalent to this
Perl one-liner removing duplicate lines in a file (without
sorting it at
first) :perl -ne'$s{$_}++||print' infile >outfile
I guess uniq method could be used, but I can't find how.
Many thanks in advance,
--
Damien Wyart
__________________________________
Yahoo! Mail - PC Magazine Editors' Choice 2005
Damien Wyart wrote:
Hello,
Converting from Perl to Ruby, I am trying to find an equivalent to this
Perl one-liner removing duplicate lines in a file (without sorting it at
first) :perl -ne'$s{$_}++||print' infile >outfile
I guess uniq method could be used, but I can't find how.
true,
open(outfile, 'w'){|out| out << IO.readlines(infile).uniq.join}
cheers
Simon
Damien Wyart <damien.wyart@free.fr> writes:
Hello,
Converting from Perl to Ruby, I am trying to find an equivalent to this
Perl one-liner removing duplicate lines in a file (without sorting it at
first) :perl -ne'$s{$_}++||print' infile >outfile
ruby -ne 'BEGIN{$s={}};$s[$_] ||= !puts($_)'
Not exactly nice, though.
Many thanks in advance,
Damien Wyart
--
Christian Neukirchen <chneukirchen@gmail.com> http://chneukirchen.org
How about the uniq(1) program? uniq infile > outfile
ruby -ne 'BEGIN{$s={}};$s[$_]=nil;END{puts$s}' infile > outfile
On 10/6/05, Damien Wyart <damien.wyart@free.fr> wrote:
Hello,
Converting from Perl to Ruby, I am trying to find an equivalent to this
Perl one-liner removing duplicate lines in a file (without sorting it at
first) :perl -ne'$s{$_}++||print' infile >outfile
I guess uniq method could be used, but I can't find how.
Many thanks in advance,
--
Damien Wyart
Damien Wyart wrote:
Hello,
Converting from Perl to Ruby, I am trying to find an equivalent to this
Perl one-liner removing duplicate lines in a file (without sorting it at
first) :perl -ne'$s{$_}++||print' infile >outfile
awk '!a[$0]++' infile >outfile
Many thanks to everyone who responded, the answers are very interesting
and enlightening !
--
Damien Wyart
ruby -e 'require "set" ; s = Set.new ; ARGF.each_line {|z| s.add?(z)
and puts(z) }' input > output
or even more verbose
ruby -e 'require "set" ; s = Set.new ; ARGF.each_line {|z| if s.add?(z)
then puts(z) end }' input > output
Tris
or:
ruby -e 'puts ARGF.readlines.uniq' infile > outfile
On Wednesday 05 October 2005 22:25, Ryan Leavengood wrote:
On 10/5/05, Damien Wyart <damien.wyart@free.fr> wrote:
> Hello,
>
> Converting from Perl to Ruby, I am trying to find an equivalent
> to this Perl one-liner removing duplicate lines in a file
> (without sorting it at first) :
>
> perl -ne'$s{$_}++||print' infile >outfile
>
> I guess uniq method could be used, but I can't find how.I tried creating a version that mimics the Perl one (because Ruby
also has the -n option), but in the end this seemed easier (and
much more readable):ruby -e "puts IO.readlines(ARGV[0]).uniq" infile > outfile
--
Stefan
Just for sake of comparison, here is the more "Perl-like" version:
ruby -ne "s||={};s[$_]||print;s[$_]=1" infile > outfile
Maybe some Ruby golfers can shorten it some more, but since Ruby lacks
some of the more terse (and obfuscating) features of Perl, it may not
be possible.
Ryan
On 10/5/05, Ryan Leavengood <leavengood@gmail.com> wrote:
I tried creating a version that mimics the Perl one (because Ruby also
has the -n option), but in the end this seemed easier (and much more
readable):ruby -e "puts IO.readlines(ARGV[0]).uniq" infile > outfile
So you are right about using uniq.
That slurps the file though, of course, so mind your memory requirements.
Here's a more direct translation (untested):
ruby -ne 'BEGIN { $lines = Hash.new(0) }; print if ($lines[$_] += 1) == 1' infile > outfile
James Edward Gray II
On Oct 5, 2005, at 3:25 PM, Ryan Leavengood wrote:
On 10/5/05, Damien Wyart <damien.wyart@free.fr> wrote:
Hello,
Converting from Perl to Ruby, I am trying to find an equivalent to this
Perl one-liner removing duplicate lines in a file (without sorting it at
first) :perl -ne'$s{$_}++||print' infile >outfile
I guess uniq method could be used, but I can't find how.
I tried creating a version that mimics the Perl one (because Ruby also
has the -n option), but in the end this seemed easier (and much more
readable):ruby -e "puts IO.readlines(ARGV[0]).uniq" infile > outfile
So you are right about using uniq.
How about the uniq(1) program? uniq infile > outfile
Converting from Perl to Ruby, I am trying to find an equivalent to this
Perl one-liner removing duplicate lines in a file (without sorting it at
first) :
He doesn't want sort the file first =)
On 10/5/05, Vincent Foley <vfoley@gmail.com> wrote:
My head a splode. Old school.
Regards,
jeremy
On Oct 5, 2005, at 7:11 PM, William James wrote:
Damien Wyart wrote:
Converting from Perl to Ruby, I am trying to find an equivalent to this
Perl one-liner removing duplicate lines in a file (without sorting it at
first) :perl -ne'$s{$_}++||print' infile >outfile
awk '!a[$0]++' infile >outfile
* "William James" <w_a_x_man@yahoo.com> in comp.lang.ruby:
awk '!a[$0]++' infile >outfile
This one is very nice, thanks ! I had an Awk version which was slightly
longer.
--
Damien Wyart
* "Vincent Foley" <vfoley@gmail.com> in comp.lang.ruby:
How about the uniq(1) program? uniq infile > outfile
Using uniq is not stable, ie you have to use sort(1) before, and the
initial order of lines is not kept.
--
Damien Wyart
Damien Wyart wrote:
Many thanks to everyone who responded, the answers are very
interesting and enlightening !
As far as I can see noone used the Hash with block feature. So here it
is:
ruby -e 'h=Hash.new(){|ha,l| puts l;ha[l.freeze]=1};ARGF.each {|l| h[l]}'
(David, I'm sorry again this is no #inject solution.)
Kind regards
robert
Here's a derived version (is this really Ruby?):
ruby -e'$><<[*$<].uniq' infile > outfile
cheers,
Mark
On 10/5/05, Ryan Leavengood <leavengood@gmail.com> wrote:
On 10/5/05, Damien Wyart <damien.wyart@free.fr> wrote:
> Hello,
>
> Converting from Perl to Ruby, I am trying to find an equivalent to this
> Perl one-liner removing duplicate lines in a file (without sorting it at
> first) :
>
> perl -ne'$s{$_}++||print' infile >outfile
>
> I guess uniq method could be used, but I can't find how.I tried creating a version that mimics the Perl one (because Ruby also
has the -n option), but in the end this seemed easier (and much more
readable):ruby -e "puts IO.readlines(ARGV[0]).uniq" infile > outfile
So you are right about using uniq.
ruby -ne 'a||={};a[$_]||=(print;1)' infile > outfile
On Wednesday 05 October 2005 22:34, Ryan Leavengood wrote:
On 10/5/05, Ryan Leavengood <leavengood@gmail.com> wrote:
> I tried creating a version that mimics the Perl one (because Ruby
> also has the -n option), but in the end this seemed easier (and
> much more readable):
>
> ruby -e "puts IO.readlines(ARGV[0]).uniq" infile > outfile
>
> So you are right about using uniq.Just for sake of comparison, here is the more "Perl-like" version:
ruby -ne "s||={};s[$_]||print;s[$_]=1" infile > outfile
Maybe some Ruby golfers can shorten it some more, but since Ruby
lacks some of the more terse (and obfuscating) features of Perl, it
may not be possible.
--
Stefan