Re: perl one liner to replace matching string

With warnings:

use strict;
use warnings;

while (<DATA>)
{
    s/(@Filetyp\s*?:)/\1c/;
    print;
}

__DATA__
@header_start
@Titel         : init 
@Filename      : test.c
@Filetyp       :
@Version       : 0001
@Produkt       : xx
@delivery      : xx
@date          : 20160610
@header_end
[download]

Output:

 0:54 >perl 1895_SoPW.pl
Possible unintended interpolation of @Filetyp in string at 1895_SoPW.p
+l line 18.
\1 better written as $1 at 1895_SoPW.pl line 18.
Global symbol "@Filetyp" requires explicit package name (did you forge
+t to declare "my @Filetyp"?) at 1895_SoPW.pl line 18.
Execution of 1895_SoPW.pl aborted due to compilation errors.

17:41 >
[download]

Perl sees @Filetyp as an (empty) array. Escape the sigil (and change \1 to $1):

s/(\@Filetyp\s*?:)/$1 c/;.

Output:

17:44 >perl 1895_SoPW.pl
@header_start
@Titel         : init
@Filename      : test.c
@Filetyp       : c
@Version       : 0001
@Produkt       : xx
@delivery      : xx
@date          : 20160610
@header_end

17:44 >
[download]

Hope that helps,

Athanasius <°(((>< contra mundum Iustus alius egestas vitae, eros Piratica,

Comment on Re: perl one liner to replace matching string Select or Download Code

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Re^2: perl one liner to replace matching string
by vinoth.ree (Monsignor) on Jun 10, 2018 at 08:05 UTC

I tried the below perl one liner to replace the "@Filetyp :" as "@Filetyp :c"

my $ext='c';
qx("perl -p -i -e \"s/(\@Filetyp\\s*?:)/\\1$ext/\" /path/test.c");
[download]

I am already doing it.Could you pls try like above perl one liner to replace the string?

All is well. I learn by answering your questions...

[reply]
[d/l]

Re^3: perl one liner to replace matching string

by Athanasius (Archbishop) on Jun 10, 2018 at 08:28 UTC

Ok, I get the same result as you reported. Playing around with it, I had to add two additional backslashes to get it to work as desired (not sure why):

my $ext='c';
qx("perl -p -i.bak -e \"s/(\\\@Filetyp\\s*?:)/\\1$ext/\" ./path/test.c
+");
#                          ^^
[download]

(Note: I also had to specify an extension for the backup file.) This is on Windows; if your O/S is different, it may treat the backslashes differently.

Hope that helps,

Athanasius <°(((>< contra mundum Iustus alius egestas vitae, eros Piratica,

[reply]
[d/l]

Re^4: perl one liner to replace matching string

by Veltro (Hermit) on Jun 10, 2018 at 20:06 UTC

not sure why

Similar findings: here and it was pretty heavily analyzed by AnomalousMonk in the following posts

[reply]

Re^4: perl one liner to replace matching string

by vinoth.ree (Monsignor) on Jun 10, 2018 at 16:58 UTC

You are right I am writing this for windows, If it is linux/unix I could have used sed/awk.

All is well. I learn by answering your questions...

[reply]
[d/l]

Re^5: perl one liner to replace matching string

by AnomalousMonk (Archbishop) on Jun 10, 2018 at 18:44 UTC


Perl: the Markov chain saw
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