[Python-ideas] Draft PEP on string interpolation

[Ron Adam]

On 08/26/2015 07:56 AM, Eric V. Smith wrote:
> I think your example below is a functional subset of what I have on
> bitbucket. The only real distinction is that I can do substitutions from
> a different string, using the expressions that were originally evaluated
> when the i-string was constructed. This is needed for the i18n case. I
> realize i18n might never use this, but it's a useful thought experiment
> in any case.

In my example... the literal and value parts of the strings are stored 
as strings in two different lists, so you can still apply an i18n 
translator to just the literal parts, or to the value parts, or to both. 
  It just needs another method.  If it's done as a property it could be 
spelled...

    s = 'string'
    i'This {s} will be translated'._


A nice improvement to that would be to add a literal quote ability to 
the format language.

   i'This {"string":Q} will be translated'.+

It allows marking parts of a string to not translate without needing to 
set it an external (to the string) variable as the example above does. 
Adding a raw quote option, RQ, would help in the cases of html and 
regular expressions.  (as your's does), but it seems this would be a 
good addition to the format language so it would work with regular 
strings too.


I don't have time to test yours this morning, but What happens in this case?

     x = [1]
     ix = i('{x}')
     x = [2]          # Mutates i-string content?
     print(str(ix))

Does this print "[1]" or "[2]"?

Cheers,
    Ron