I got a string $ou "# PATH=$PATH:$NAS_DB/sbin:$NAS_DB/bin:$NAS_DB/sbin" and want to delete the heading # and the white space around.

 my $ou ="# PATH=\$PATH:\$NAS_DB/sbin:\$NAS_DB/bin:\$NAS_DB/sbin";
print __FILE__." line".__LINE__." trace: ".$ou."\n";
if($ou =~ /^\s*#\s*(PATH=.*\$NAS_DB\/bin.*)$/)
{
my $str = $1;
$ou=~s/^\s*#\s*PATH=.*\$NAS_DB\/bin.*$/$str/;
print __FILE__." line".__LINE__." trace: ".$ou."\n";
}

[download]

When I remove $str, replace it with $1, the output is empty. Not what I want. So why? Every thanks.

 my $ou ="# PATH=\$PATH:\$NAS_DB/sbin:\$NAS_DB/bin:\$NAS_DB/sbin";
print __FILE__." line".__LINE__." trace: ".$ou."\n";
if($ou =~ /^\s*#\s*(PATH=.*\$NAS_DB\/bin.*)$/)
{
$ou=~s/^\s*#\s*PATH=.*\$NAS_DB\/bin.*$/$1/;
print __FILE__." line".__LINE__." trace: ".$ou."\n";
}

[download]
OK, I got it. Seems $1 was reset after every matching.

In reply to regex substitute(resolved) by anaconda_wly

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