I would be very greatful if someone could give me a detailed description of the following regular expression:

s/([^\0-\x7F])/do {my $o = ord($1); sprintf("%c%c", 0xc0 | ($o >> 6), 0x80 | ($o & 0x3f)) }/ge

The above is the meat from a uri_escape_utf8 subroutine. I get the gist of what is going on; we're converting a utf-encoded string to its corresponding ASCII only uri representation. Furthermore,

First we capture any character whose hex representation does not fall within the range specified by the negative character class [^\0-\x7F] (Which comprises the basic ASCII character set, I think).

Next every time we grab a legal character, we store the numeric value of our character in $o, then we sprintf the conversion... But I don't know exactly what is going on in the sprintf statement...

I want to do something similar, convert all full and half width latin characters (0x0FF00-0x0FF5E) to their more common ASCII representations (0x00020-0x0007F), so any lucid explanation of the above code, or alternatively, how to directly solve my problem, will be greatly appreciated!!

P.S. I know I can do this with a hash of corresponding values, I'm hoping there is something shorter and more interesting.

In reply to Intra-Unicode Conversions by kettle

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