Re: [icu-design] proposal: extend plural format syntax

[Markus S. <mar...@gm...>]

I found an issue that is unavoidable and should be documented. I expect that
this will be very rare because I think most people will just write # for the
number inside a PluralFormat. But if they don't --

Consider this message:
      "I see {0, plural, offset:1 "
          "=0 {no one at all}"
          "=1 {{1}}"
          "one {{1} and one other person}"
          "other {{1} and *{0, number,##,##.00}* other people}} "
      "in {2}."
Note that the "other" clause does not use a simple # but a "fancy"
NumberFormat pattern. Due to the way MessageFormat and
PluralFormat/ChoiceFormat/SelectFormat work together , this {0, number, ...}
sees the value *without offset adjustment*.

With arguments (200, "Asterix", "Lutetia") you get  "I see Asterix and
2,00.00 other people in Lutetia."
Rather than the offset-adjusted 199=1,99.00.

We should also document the workaround: Use a different placeholder that is
manually offset-adjusted. For example:
      "I see {0, plural, offset:1 "
          "=0 {no one at all}"
          "=1 {{2}}"
          "one {{2} and one other person}"
          "other {{2} and *{1, number,##,##.00}* other people}} "
      "in {3}."
Now, with
  int value = 200;
  int value_minus_offset = value - 1;
and MessageFormat arguments of (value, value_minus_offset, "Obelix",
"Helvetia") you get  "I see Obelix and 1,99.00 other people in Helvetia."

markus