<div class="gmail_quote">On Wed, Aug 31, 2011 at 11:51 AM, Glenn Linderman <span dir="ltr"><<a href="mailto:v%2Bpython@g.nevcal.com">v+python@g.nevcal.com</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex;">
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On 8/31/2011 10:12 AM, Guido van Rossum wrote:
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<pre>On Wed, Aug 31, 2011 at 1:09 AM, Glenn Linderman <a href="mailto:v+python@g.nevcal.com" target="_blank"><v+python@g.nevcal.com></a> wrote:
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<pre>So from reading all this discussion, I think this point is rather a key
one... and it has been made repeatedly in different ways: Arrays are not
suitable for manipulating Unicode character sequences, and the str type is
an array with a veneer of text manipulation operations, which do not, and
cannot, by themselves, efficiently implement Unicode character sequences.
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<pre>I think this is too strong. The str type is indeed an array, and you
can build useful Unicode manipulation APIs on top of it. Just like
bytes are not UTF-8, but can be used to represent UTF-8 and a
fully-compliant UTF-8 codec can be implemented on top of it.
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This statement is a logical conclusion of arguments presented in
this thread.<br>
<br>
1) Applications that wish to do grapheme access, wish to do it by
grapheme array indexing, because that is the efficient way to do it.<br></div></blockquote><div><br>I don't believe that should be taken as gospel. In Perl, they don't do array indexing on strings at all, and use regex matching instead. An API that uses some kind of cursor on a string might work fine in Python too (for grapheme matching).<br>
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2) As long as str is restricted to holding Unicode code units or
code points, then it cannot support grapheme array indexing
efficiently.<br>
<br>
I have not declared that useful Unicode manipulations APIs cannot
be built on top of str, only that efficiency will suffer.<br>
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</blockquote></div><br>But you have not proven it.<br clear="all"><br>-- <br>--Guido van Rossum (<a href="http://python.org/~guido">python.org/~guido</a>)<br>