Unicode Conversion

[panky245]

Hi, I am a newbie in Perl. Does anybody seems an error in my
following snippet. I am regularly getting the compilation error in it.
$char_lpar = "\x{00028}";
$char_rpar = "\x{00029}";
my $decval_1 = ord $char_lpar;
my $decval_2 = ord $char_rpar;

$data =~ s/$char_lpar/sprintf("&#x%.4x;", $decval_1)/ge;
$data =~ s/$char_rpar/sprintf("&#x%.4x;", $decval_2)/ge;

Best,

Pankaj Chaturvedi

[haoess]

$char_lpar and $char_rpar get interpolated inside your substitution. You can quote them using the \Q\E construct:

$data =~ s/\Q$char_lpar\E/sprintf("%.4x;", $decval_1)/ge;
$data =~ s/\Q$char_rpar\E/sprintf("%.4x;", $decval_2)/ge;

-- Frank

[graff]

What you got was not a "compilation error" -- the code snippet compiles just fine. You got a "run-time error", which (as the name implies) only happens when you try to run the script.

If you want to replace any character whatever with its hex-numeric entity reference, you can do it like this:

my $num_ent_chars = "()";  # add other characters as needed, but ^ - [
+ ] are special
$data =~ s/([$num_ent_chars])/sprintf("&#x%4x;",ord($1))/ge;

Since the string contained in $num_ent_chars is being used inside square brackets in the regex (to define a character class), most of the regex-magic meanings for things like ".", "*", "?", "+" etc do not apply. You just need to be careful when the character class has to include square brackets, hyphen and caret -- either escape these with "\", or place them carefully -- for example:

perl -le '$_="me [ and ] you ^ and - him";  $c="][^-";  s/[$c]/xxx/g; 
+ print'

will print "me xxx and xxx you xxx and xxx him".

[ikegami]

I am regularly getting the compilation error in it.

There's a good reason why error message don't just say "An error happened!". Why don't you tell us what error you are getting.

That said, haoess already identified a major source of error.