Forum: Ruby Data stream variables

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Alain H. (Guest)
on 2009-01-12 15:22
Hi

I want to print all lines wihtch contains the string "Open" from a bunch
of 'xml' files. Additionally I want to print the filename and the line
number of the match.

The problem with the following snippet is, that the variable '$.' does
not reset the line number at the beginning of a new file.

That menas, the printed file numbers are not correct except for the
first file of '*.xml'

ruby -n -e 'puts ($FILENAME + " " + $..to_s + "" + $_) if /Open/' *.xml

Does anybody have a idea, on how to print the correct line number?

Thanks a lot for your answer, Alain.
Andrew T. (Guest)
on 2009-01-12 15:39
(Received via mailing list)
On Mon, Jan 12, 2009 at 3:21 PM, Alain H.
<removed_email_address@domain.invalid
> wrote:

> first file of '*.xml'
>
> ruby -n -e 'puts ($FILENAME + " " + $..to_s + "" + $_) if /Open/' *.xml
>
> Does anybody have a idea, on how to print the correct line number?
>
> Thanks a lot for your answer, Alain.
> --
> Posted via http://www.ruby-forum.com/.
>
>
Does it all have to be done in ruby?
Why not
ls *.xml | xargs ruby -n -e 'puts ($FILENAME + " " + $..to_s + "" + $_)
if
/Open/'

--
Andrew T.
http://ramblingsonrails.com
http://www.linkedin.com/in/andrewtimberlake

"I have never let my schooling interfere with my education" - Mark Twain
Alain H. (Guest)
on 2009-01-12 16:46
Andrew T. wrote:
> On Mon, Jan 12, 2009 at 3:21 PM, Alain H.
> <removed_email_address@domain.invalid
>> wrote:
>
>> first file of '*.xml'
>>
>> ruby -n -e 'puts ($FILENAME + " " + $..to_s + "" + $_) if /Open/' *.xml
>>
>> Does anybody have a idea, on how to print the correct line number?
>>
>> Thanks a lot for your answer, Alain.
>> --
>> Posted via http://www.ruby-forum.com/.
>>
>>
> Does it all have to be done in ruby?
> Why not
> ls *.xml | xargs ruby -n -e 'puts ($FILENAME + " " + $..to_s + "" + $_)
> if
> /Open/'
>
> --
> Andrew T.
> http://ramblingsonrails.com
> http://www.linkedin.com/in/andrewtimberlake
>
> "I have never let my schooling interfere with my education" - Mark Twain

Thanks a lot for your answer.

Sadly I'm running Windows XP.

But I try to get GnuWin32 running...

Alain
Andrew T. (Guest)
on 2009-01-12 17:29
(Received via mailing list)
On Mon, Jan 12, 2009 at 4:45 PM, Alain H.
<removed_email_address@domain.invalid
> wrote:

> >>
> >
>
> But I try to get GnuWin32 running...
>
> Alain
> --
> Posted via http://www.ruby-forum.com/.
>
>
Alain

Sorry, I made a mistake with my answer above. Instead of using xargs
(which
was exactly the same as your method - actually)
Use find to make sure ruby gets a unique file each time:
find *.xml -exec ruby -n -e 'puts ($FILENAME + " " + $..to_s + "" + $_)
if
/Open/' {} \;
--still doesn't help on Windows though

Instead of trying to do this in a one-liner, save the following as a
file:
ARGV.each do |filename|
  File.open(File.join(File.dirname(__FILE__), filename)) do |file|
    while line = file.gets
      puts (filename + " " + $..to_s + "" + $_) if line =~ /Open/
    end
  end
end

And then run:
ruby <filename> *.xml

Hopefully that helps

--
Andrew T.
http://ramblingsonrails.com
http://www.linkedin.com/in/andrewtimberlake

"I have never let my schooling interfere with my education" - Mark Twain
Robert K. (Guest)
on 2009-01-12 21:15
(Received via mailing list)
On 12.01.2009 14:21, Alain H. wrote:
> ruby -n -e 'puts ($FILENAME + " " + $..to_s + "" + $_) if /Open/' *.xml
>
> Does anybody have a idea, on how to print the correct line number?
>
> Thanks a lot for your answer, Alain.

I'm not Alain, but... :-)  Just kidding.

Here's how to do it:

ruby -ne 'puts "#$FILENAME #$. #$_" if /Open/; $.=0 if ARGF.eof?' *.xml

Cheers

  robert
Andrew T. (Guest)
on 2009-01-12 21:34
(Received via mailing list)
On Mon, Jan 12, 2009 at 9:14 PM, Robert K.
<removed_email_address@domain.invalid>wrote:

>> first file of '*.xml'
> Here's how to do it:
>
I was wondering if you could reset the line counter but didn't think of
just
setting $. = 0
Sometimes ruby is just too easy :-) I still sometimes think things need
to
be more complicated.

--
Andrew T.
http://ramblingsonrails.com
http://www.linkedin.com/in/andrewtimberlake

"I have never let my schooling interfere with my education" - Mark Twain
Robert K. (Guest)
on 2009-01-12 21:45
(Received via mailing list)
On 12.01.2009 20:33, Andrew T. wrote:
>>>
>>> Thanks a lot for your answer, Alain.
>>>
>> I'm not Alain, but... :-)  Just kidding.
>>
>> Here's how to do it:
>>
>> ruby -ne 'puts "#$FILENAME #$. #$_" if /Open/; $.=0 if ARGF.eof?' *.xml
>>
> I was wondering if you could reset the line counter but didn't think of just
> setting $. = 0

IMHO the tricky bit is to know *when* to reset, i.e. to know that
ARGF#eof? signals the end of a single file and not all files. :-)

> Sometimes ruby is just too easy :-) I still sometimes think things need to
> be more complicated.

:-) The other area where I simplified your piece of code is the string
handling.  Btw, when String interpolation (i.e. #$GLOBAL or #{expr}) you
do not need the explicit to_s.

Kind regards

  robert
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