Thank you for this report @olivere! Kindly paging @mpvl

@odeke-em Can I work on this issue?

@vikramcse, all yours and thank you!

@bcmills @odeke-em Hello there
Here are my findings

1. I think in file gen_common.go, the ordering of the constants is wrong. The ordering should be like this.

const (
	Zero Form = iota
	One
	Two
	Few
	Many
        Other
)

I did try changing above constants structure and run go generate but it did not solved problem.

3. Let's consider below test case

message.Set(language.English, "%d files remaining",
		plural.Selectf(1, "%d",
			plural.Two, "2 files remaining",
		))

p := message.NewPrinter(language.English)
p.Printf("%d files remaining", 2)

In above case we are passing plural.Two as a case which has byte value 3 (because of the wrong order).
The selector type 3 does not match the valid cardinal rules list in this case which is [0, 2] which is returned by validForms function; further the valid list is used by this code but it's throwing error s:"plural: form '\x03' not supported for language "en"" as the value 3 does not match with [0, 2]

I am not sure how to take this further.

EDIT:
Hi @mpvl, i need some help to solve this issue.

Thanks

I need some help to solve this issue.

@mpvl is the right person to help. (He's the primary owner of x/text.)

Other has special meaning in CLDR and really should be 0. But I will look in to this.

This issue is the following: linguistically, English doesn't have a "Zero" plural form, only "One" and "Other" (singular and anything else). Like with ICU, the Go implementation of plurals allows matching to specific numeric values, like =0, but this is not the same as plural.Zero, which will never match in English or, in the example, Dutch.

In general, the linguistic plural categories are just names and may often not correspond one-to-one to a particular number. For instance, in Croatian the numbers 1, 21, and 101 are all considered to be plural.One. So "one" and plural.One are equivalent, but "=1" and plural.One, in general, are not.

So this is partly a documentation and naming issue. Using plural.Singular instead of plural.One, for instance, would have been clearer, in English. However, that approach wouldn't scale. The numeric names only loosely match a myriad of plural categories in different languages.

The documentation states that the plural categories do not correspond one-to-one with numbers. The naming is also the standard naming from ICU/CLDR. But I'm open to suggestions as to how to make this clearer.

working as intended.