in reply to Re: Re: Re: Re: regex for utf-8
in thread regex for utf-8

I am wrapping my head around the bit-masking and conditional bit-shifting I need to do to extract the actual value of the code. The czyborra site http://czyborra.com/utf/ is invaluable, but my head is thick. How do I march down from the high bit of the first byte, testing and then extracting the hex codes from the succeeding bits?
That's what unpack "U*" does.

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Re: Re: Re: Re: Re: Re: regex for utf-8
by Anonymous Monk on Feb 28, 2003 at 22:58 UTC
    I have RTFM'ed pack() and unpack(), but don't understand its use in this context. What is the "TEMPLATE" being used here? 
    unpack TEMPLATE,EXPR
unpack does the reverse of pack: it takes a string and expands it out 
+into a list of values. (In scalar context, it returns merely the firs
+t value produced.)

    [download]
    This line in the manual I find obscure as well, though it seems it would help me if I understood it: 
    sub ordinal { unpack("c",$_[0]); } # same as ord()

    [download]
    Could you explain unpack "U*"? What is the "U"? (something to do with Unicode? I listened to "Well you needn't" (angular piano music)last night in celebration of the post showing the table for converting with cp 1252
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[d/l]
[select]
      I see that "pack()" is a little more expressive than "unpack()" in the manual. Sorry for the question asked before reading all i could.
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