[Python-ideas] Add "htmlcharrefreplace" error handler

[M.-A. Lemburg]

On 14.06.2013 01:37, Ezio Melotti wrote:
> Hi,
> 
> On Tue, Jun 11, 2013 at 5:49 PM, Serhiy Storchaka <storchaka at gmail.com> wrote:
>> I propose to add "htmlcharrefreplace" error handler which is similar to
>> "xmlcharrefreplace" error handler but use html entity names if possible.
>>
>>>>> '∀ x∈ℜ'.encode('ascii', 'xmlcharrefreplace')
>> b'∀ x∈ℜ'
>>>>> '∀ x∈ℜ'.encode('ascii', 'htmlcharrefreplace')
>> b'∀ x∈ℜ'
>>
> 
> Do you have any use cases for this, or is it just for completeness
> since we already have xmlcharrefreplace?

The purpose is the same, but in a different, also very common context.

As for use cases, you already pointed out quite a few below and
I'm adding a few more.

> IMHO character references (named or numerical) should never be used in
> HTML (with the exception of " > and <).
> They exist mainly for three reasons:
> 1) provide a way to include characters that are not available in the
> used encoding (e.g. if you are using an obsolete encoding like
> windows-1252 but still want to use "fancy" characters);
> 2) to keep the HTML source ASCII-only;

This is the main reason for using them. HTML's default encoding
is Latin-1, unlike XML.

> 3) to specify a character by name if it's not possible to enter it
> directly (e.g. you don't know the keys combinations);

They exist for the same reason you have named Unicode
characters: to make it obvious which character you are using
without having to rely on a specific encoding.

Another reason to use them is that a user might not have the
needed fonts to display the characters in question.

And in some cases, you also need to use the references to escape
certain characters from being interpreted using their
HTML meaning, e.g. & and the ones you've given above. But
that's not the use case for the error handler.

-- 
Marc-Andre Lemburg
eGenix.com

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