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Full Discussion: Perl newbie - regex replace all groups issue
Top Forums Shell Programming and Scripting Perl newbie - regex replace all groups issue Post 302585412 by birei on Wednesday 28th of December 2011 10:32:24 AM
Old 12-28-2011
Hi samask,

Some issues:

1.- while (<>) reads one line at a time and your regex tries to work over multiple lines.
2.- '^' marks the beginning of the line and it is zero-width, put it out of the parentheses.
3.- There is no need of the 'g' switch. Your regex only will match at most once.
4.- No need of 'i' switch. You are not using any alphabetic character.

One solution:

Code:
$ cat script.pl
use warnings;
use strict;

local $/;
my $file = <>;
$file =~ s/^(.*)\n^(~+)/## $1/m;
print $file;
$ cat infile
The Vedanta Philosophy
~~~~~~~~~~~~~~~

Body text
$ perl script.pl infile
## The Vedanta Philosophy

Body text

Regards,
Birei
This User Gave Thanks to birei For This Post:
samask
 

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LEARN ABOUT OPENSOLARIS

shcomp

shcomp(1)							   User Commands							 shcomp(1)

NAME

       shcomp - compile a ksh93 shell script

SYNOPSIS

       shcomp [-nv] [infile [outfile]]

       shcomp -D [infile [outfile]]

DESCRIPTION

       If  the	-D  option  is not specified, shcomp takes a shell script, infile, and creates a binary format file, outfile, that ksh93 reads and
       executes with the same effect as the original script.

       Aliases are processed as the script is read. Alias definitions whose value requires variable expansion will not work correctly.

OPTIONS

       The following options are supported:

       -D	       Generate a list of strings that need to be placed in a message catalog for internationalization.
       --dictionary
		       With this option, all double quoted strings that are preceded by $ are printed, one literal  per  line.	A  literal  $"foo"
		       prints  "foo" in the output. These are the messages that need to be translated to locale specific versions for internation-
		       alization.

       -n	       Display warning messages for obsolete or non-conforming constructs.
       --noexec

       -v	       Display input from infile onto standard error as it reads it.
       --verbose

OPERANDS

       The following operands are supported:

       infile	  Specifies the name of the file that contains the shell script to be used as input.

		  If infile is omitted, the shell script is read from standard input.

       outfile	  Specifies the name of the output file.

		  If outfile is omitted, both modes write their results to standard output.

EXIT STATUS

       The following exit values are returned:

       0     Successful completion.

       >0    An error occurred.

ATTRIBUTES

       See attributes(5) for descriptions of the following attributes:

       +-----------------------------+-----------------------------+
       |      ATTRIBUTE TYPE	     |	    ATTRIBUTE VALUE	   |
       +-----------------------------+-----------------------------+
       |Availability		     |SUNWcsu			   |
       +-----------------------------+-----------------------------+
       |CSI			     |Enabled			   |
       +-----------------------------+-----------------------------+
       |Interface Stability	     |See below.		   |
       +-----------------------------+-----------------------------+

       The command-line interface and the system variables are Committed. The compiled shell code format is Private. The output of the	-D  option
       is Volatile.

SEE ALSO

       ksh93(1), attributes(5)

SunOS 5.11							    27 Jan 2009 							 shcomp(1)
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