in reply to hex in regexp

The standard way is to do this is like the following: 

$ perl -Mstrict -Mwarnings -E '
> my $x = q{X-X!X?X};
> $x =~ s/([[:^upper:]])/unpack q{H2}, $1/eg;
> say $x;
> '
X2dX21X3fX

[download]

Note: I used upper instead of ascii for my example code.

There may be modules that also supply this functionality. If there are, I'm sure other monks will provide details.

-- Ken

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Re^2: hex in regexp
by shamanoff (Initiate) on May 22, 2012 at 05:04 UTC

    Thank you Ken! Your code almost worked. The thing is that for some reason it didn't substitute the symbols with their hex-codes, but just removed them from the string. For example please see the example of the string I'm trying to modify: "çe quil Y a Yå" I am still testing trying to figure out why it happened. Additional question - how exactly can I wrap the hex code in a <> brackets in this example?

[reply]

      Changing upper to ascii and using your string, I get: 

      $ perl -Mstrict -Mwarnings -E '
my $x = q{çe quil Y a Yå};
$x =~ s/([[:^ascii:]])/unpack q{H2}, $1/eg;
say $x;
'
c383c2a7e quil Y a Yc383c2a5

      [download]

      Check that you didn't make a typo when entering your code. If you are still having problems, please post your code - as it is, I can't reproduce your problem.

      To wrap the codes in < and >, or any other characters, you can just concatenate the characters at the beginning and end of the hex code: 

      $ perl -Mstrict -Mwarnings -E '
my $x = q{çe quil Y a Yå};
$x =~ s/([[:^ascii:]])/q{<} . unpack(q{H2}, $1) . q{>}/eg;
say $x;
'
<c3><83><c2><a7>e quil Y a Y<c3><83><c2><a5>

      [download]

      -- Ken

[reply]
[d/l]
[select]
        I double checked the code and haven't found any typo: 
        #!/usr/bin/perl

$file = @ARGV[0];
$out_file = $file.".out";
my $count = 0;

print "Processing file: $file\n";
print "Output file: $out_file\n";

open FILE, "$file" or die "cannot open $file file";
open OUT, ">>$out_file" or die "cannot create $out_file file";

#go through the file rows
while (<FILE>) {
        chomp;
        # if row contain non-ASCII symbols - it is counted
        if ($_ =~ /[[:^ascii:]]/) {

                print "String before modification:\n $_ \n";

                s/[[:^ascii:]]/q{<} . unpack(q{H2}, $1) . q{>}/eg;

                print "String after modification:\n $_ \n";
                print OUT "$_\n";
                $count++ ; }
        else {
                print OUT "$_\n";
        }
}

print "there are $count possibly corrupted rows\n";

close FILE;
close OUT;

        [download]
        the contents of processed file: 
        0,1,,,1,~=_<>}[]||$? £??§^`??¿  ?. Qu est  çe quil Y a Yå,0,20120
+306101731
0,1,,,1,Teá,0,20120314104403
0,1,,,1,Q<8a>rUì ,0,20120306103345
1,1,,,3,,0,20120331152610
1,1,,,3,,0,20120331152612

        [download]
[reply]
[d/l]
[select]
        Thanks, Ken! I found the typo - forgot to put the search expression in brackets ([...]). Let me say that I am sorry for my impatience. :)
[reply]

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