From: "John W. Krahn" <[EMAIL PROTECTED]>
> Jenda Krynicky wrote:
> > From: "John W. Krahn" <[EMAIL PROTECTED]>
> >> Rob Dixon wrote:
> >>> obdulio santana wrote:
> >>>> May be this helps
> >>>>
> >>>> perl -lne "print if ++$D{$_} == 1" address.txt
> >>> You may prefer the cuteness of
> >>>
> >>> perl -lne "print unless $D{$_}++" address.txt
> >> Or the shortness of:
> >>
> >> perl -ne'$D{$_}++||print' address.txt
> >
> > Actually this
> >
> > perl -n'${$_}||=print'
> >
> > works as well as long as the last line in the file either does end
> > with a newline or doesn't match any builtin variable whose default
> > value is already true.
> >
> > One more keystroke down.
>
> $ perl -c -n'$D{$_}++||print'
> Unrecognized switch: -$D{$_}++||print (-h will show valid options).
Sorry, it should have been
perl -ne'${$_}||=print'
I'm using windows so I have to test it with doublequotes in place of
the singlequotes so I must have made a mistake changing them back.
From: "Chas. Owens" <[EMAIL PROTECTED]>
> That is nasty. If I am reading that correctly you are using a
> symbolic reference to create variables with the name of the line. > I can't
> remember, does Perl have a limit on the size of a variable > name?
Yes, you are reading it correctly. And since the line contains the
newline it can't match any builtin. Except possibly for the last line
in the file.
Does it have a limit on the size of a hash key?
If it does, then the limit is high enough I believe.
Jenda
===== [EMAIL PROTECTED] === http://Jenda.Krynicky.cz =====
When it comes to wine, women and song, wizards are allowed
to get drunk and croon as much as they like.
-- Terry Pratchett in Sourcery
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