[Python-ideas] Rough draft: Proposed format specifier for a thousands separator (discussion moved from python-dev)
eric at trueblade.com
Thu Mar 12 22:24:01 CET 2009
Raymond Hettinger wrote:
> [Jim Jewett]
>> Fair enough. But what does a thousands separator provide that the "n"
>> type doesn't already provide? (Well, except that n isn't as well
>> known -- but initially this won't be either.)
> It's nice to be have a non-locale aware alternative so you can say
> explicitly what you want. This is especially helpful in Guido's example
> where you need to format for a different locale than the one that is
> currently on your machine (i.e. the global state doesn't match the target).
I've always thought that we should have a utility function which formats
a number based on the same settings that are in the locale, but not
actually use the locale. Something like:
format_number(123456787654321.123, decimal_point=',', thousands_sep=' ',
grouping=[4, 3, 2])
>>> '12 34 56 78 765 4321,123'
That would get rid of threading issues, and you wouldn't have to worry
about what locales were installed.
I basically have this function in the various formatting routines, it
just needs to be pulled out and exposed.
>> Do you really want a different type, such as "m" for money?
> I don't but I'm sure someone does. I did write a money formatter
> sample recipe for the decimal docs so people would have something
> to model from.
This becomes easier with the hypothetical "format_number" routine.
But this is all orthogonal to the str.format() discussion.
More information about the Python-ideas