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From: Serhiy Storchaka <storchaka@gmail.com>
Subject: Re: Find and Replace Simplification
Date: Sun, 21 Jul 2013 15:28:32 +0300
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21.07.13 14:29, Joshua Landau написав(ла):
> On 21 July 2013 08:44, Serhiy Storchaka <storchaka@gmail.com> wrote:
>> 20.07.13 20:03, Joshua Landau написав(ла):
>>
>>> Still, it seems to me that it should be optimizable for sensible
>>> builtin types such that .translate is significantly faster, as there's
>>> no theoretical extra work that .translate *has* to do that .replace
>>> does not, and .replace also has to rebuild the string a lot of times.
>>
>> You should analyze overall mapping and reorder items in right order (if it
>> possible), i.e. '&' should be replaced before '<' in html.escape. This extra
>> work is too large for most real input.
>
> I don't understand. What items are you reordering?

mapping.items(). We can implement s.translate({ord('<'): '&lt;', 
ord('&'): '&amp;'}) as s.replace('&', '&amp;').replace('<', '&lt;'), but 
not as s.replace('<', '&lt;').replace('&', '&amp;').