Re: Feature request: plain option for gsub

[Jonas Thiem <jonasthiem@...>]

Hm I see. Still, wouldn't a plain option be more consistent with find
and easier to use for beginners?

On Thu, Aug 21, 2014 at 4:21 PM, Roberto Ierusalimschy
<roberto@inf.puc-rio.br> wrote:
>> I think this already demonstrates my point. Coming up with a regex
>> that is safe and escapes everything is not trivial.
>>
>> [...]
>> >
>> > On my system, '%p' does not match '[+$^]', so '%p' should become '[%p+$^]'.
>
> This seems like a bug in his system (or else he is using some weird
> locale...). '%p' corresponds to 'ispunct', and the C standard says this:
>
>   In an implementation that uses the seven-bit US ASCII character set, the
>   printing characters are those whose values lie from 0x20 (space) through
>   0x7E (tilde);
>
>   [...]
>
>   In the "C" locale, ispunct returns true for every printing character for
>   which neither isspace nor isalnum is true.
>
> So, '[+$^]' must be all punctuations (and therefore match '%p').
>
> If you assume a correct libC and a sane locale, '%p' is all you need.
>
> -- Roberto
>