Fix singular/plural translation section

[jmooring]

https://gohugo.io/content-management/multilingual/#query-a-singularplural-translation

In order to meet singular/plural requirement, you must pass a dictionary (map) with a numeric .Count property to the i18n function.

No.

The function will read .Count from .ReadingTime

No.

In case you need to pass custom data: ((dict "Count" 25) is minimum requirement)

No.

Maybe some of this was true in an earlier version, but none of it is true now.

1. .ReadingTime is just an int. It doesn't have a "built-in Count" property.

2. The only way to get T/i18n to return the singular value from the translation table is to pass the integer value 1.

   {{ T "kitten" 1 }}
   

3. If you pass a float it complains.

   {{ T "kitten" 1.5 }}
   

   invalid plural count 1.5 for message id "kitten": floats should be formatted into a string

4. T/i18n always returns the plural value from the translation table when you pass a string, slice, or dict. All of these return the plural value:

   {{ T "kitten" (dict "Count" 1 "foo" "bar") }}
   {{ T "kitten" (dict "count" 1 "foo" "bar") }}
   {{ T "kitten" (dict "Count" "1" "foo" "bar") }}
   {{ T "kitten" (dict "count" "1" "foo" "bar") }}
   

[hugo v0.83.0-DEV+extended linux/amd64 BuildDate=unknown]

[jmooring]

So I think this page currently describes how go-i18n V1 behaved. We are now using go-i18n V2.

[jmooring]

The i18n files allow for more than just singular (one) and plural (other) categories, but it depends on the language.

The Unicode Common Locale Data Repository (CLDR) defines plural rules for each language. Take a look at the "cardinal" categories in this table. Examples:

Language	Code	Cardinal Categories
English	en	one, other
German	de	one, other
Irish	ga	one, two, few, many, other
Italian	it	one, other
Latvian	lv	zero, one, other
Norwegian Bokmål	nb	one, other
Norwegian Nynorsk	nn	one, other
Polish	pl	one, few, many, other
Russian	ru	one, few, many, other
Spanish	es	one, other
Welsh	cy	zero, one, two, few, many, other

The https://github.com/nicksnyder/go-i18n package handles the plural rules for Hugo, but there are few important things to remember.

1) Cardinal categories defined in the i18n file that are not defined in the CLDR plural rules will be ignored. In the example below, all but one and other will be ignored because the CLDR plural rules for English exclude the other cardinal categories.

i18n/en.toml

[cat]
zero = "kittens"      # ignored
one = "cat"
two = "kitties"       # ignored
few = "fur balls"   # ignored
many = "beasts"       # ignored
other = "cats"

2) When a cardinal category is defined in the CLDR plural rules but is missing from the i18n file, then (a) the value from the other category (if defined) will be substituted, and (b) a warning will be generated. For example, consider this Polish translation:

i18n/pl.toml

[cat]
one = "kot"
other = "koty"

The CLDR plural rules specify two additional cardinal categories for the Polish language: few and many.

Statement	Result	Warning
{{ i18n "cat" 0 }}	koty	WARN ... "cat" has no plural form "many"
{{ i18n "cat" 1 }}	kot	N/A
{{ i18n "cat" 2 }}	koty	WARN ... "cat" has no plural form "few"
{{ i18n "cat" 3 }}	koty	WARN ... "cat" has no plural form "few"
{{ i18n "cat" 4 }}	koty	WARN ... "cat" has no plural form "few"
{{ i18n "cat" 5 }}	koty	WARN ... "cat" has no plural form "many"

3) Although the current implementation of https://github.com/nicksnyder/go-i18n uses other as a fallback category when the correct category is not defined, it was never intended to be used that way. The other category is explicitly defined by the CLDR plural rules, and is an implicit fallback only when all other categories for a given language are defined.

[jmooring]

Additional info for when we (I) get around to updating this page. This comes into play when i18n is called without a quantity:

{{ i18n "cat" }}

This produces the same results as

{{ i18n "cat" 0 }} 

The Unicode Common Locale Data Repository (CLDR) defines plural rules for 208 languages.

For 165 of those languages, the cardinal category other is used when the quantity specified for the translation is zero.

The other 43 languages use a variety of cardinal categories when the quantity specified for the translation is zero, including zero, one, few, and many.

Language	Code	Cardinal Category
Akan	ak	one
Amharic	am	one
Arabic	ar	zero
Armenian	hy	one
Assamese	as	one
Bangla	bn	one
Belarusian	be	many
Bhojpuri	bho	one
Cebuano	ceb	one
Central Atlas Tamazight	tzm	one
Colognian	ksh	zero
Cornish	kw	zero
Filipino	fil	one
French	fr	one
Fulah	ff	one
Gujarati	gu	one
Gun	guw	one
Hindi	hi	one
Kabyle	kab	one
Kannada	kn	one
Langi	lag	zero
Latvian	lv	zero
Lingala	ln	one
Malagasy	mg	one
Maltese	mt	few
Manx	gv	few
Najdi Arabic	ars	zero
Nigerian Pidgin	pcm	one
Northern Sotho	nso	one
Persian	fa	one
Polish	pl	many
Portuguese	pt	one
Prussian	prg	zero
Punjabi	pa	one
Romanian	ro	few
Russian	ru	many
Sinhala	si	one
Tachelhit	shi	one
Tigrinya	ti	one
Ukranian	uk	many
Walloon	wa	one
Welsh	cy	zero
Zulu	zu	one

[jmooring]

Closing in favor of #2099.