makeKey("test", 'de', '', NA)
makeKey('de', '')

Adds a message and its translation(s) to the library-internal translation environment, see the GNU gettext manual.

options('gettext.lang'="de") # set the current language to 'de'
addMsg("Unknown system error", "Unbekannter Systemfehler")
addMsg("Unknown system error", "Error desconegut del sistema", lang="es")
addMsg("found \%d fatal error", plural="found \%d fatal errors", 
       str=c("\%d Fehler gefunden", "\%d Fehler gefunden"))
addMsg("We saw her duck", "Wir haben ihre Ente gesehen", context="duck as noun")
addMsg("We saw her duck", "Wir haben gesehen, wie sie sich duckte", context="duck as verb")

Adds a plural definition to internal translation object. It it already exists it will be overwritten.

# Czech
pl <- addPlural(text='nplurals=3; plural=(n==1) ? 0 : (n>=2 && n<=4) ? 1 : 2;')
print(pl)

Assigns a file, based on its name or a named parameter, to a language and a domain. The base name of a file is composed by a domain and language code separated by anon-letters. A language code starts with a two (ISO 639-1) letter code.

options('gettext.lang'='en')
bind('myproject_de.po')
bind(de='myproject.po')
bind(de=c('myproject1.po', 'myproject2.po'))
bind(de=c('myproject1_de.po', 'myproject2_de.po'), 
         en=c('myproject1_en.po', 'myproject2_en.po'))
files <- c("myproject_de.po", 
           "intl/for_use_owncloud_impress_cs_CZ.po",
           "intl/ibalsa-master-zh_HK.po",
           "spirit-po/test1.po")
bind(files)
bind()

Sets the path for a domain.

bindtextdomain('app2', system.file('shiny', 'app2', package='gettext'))

A data frame with two- and three letter codes from ISO 639-1 and ISO 693-2. Codes are taken from alpha-3 bibliographic, alpha-3 terminologic and alpha-2 code.

data(iso639)
head(iso639)

A list of plural forms used in PO files.

data(plural)
plural[[1]]
lang <- sapply(plural, function(v) { v$lang })
# extract arabic
ar   <- which(lang=='ar')
plural[[ar]]
# test of plural form
plural[[ar]]$plural(0:100)

Returns a copy of the internal translation environment or a list of str's of each object.

getTranslation()

Returns a translated string from the untranslated string id1. An abbreviated form is G since R does not support _ as unary operator.

gettext("I saw her duck") # no translation at all
G("I saw her duck") 

Takes a file, R code or R expression and replaces all text constants by gettext(text_constant). The replacement is not done inside gettext, G, ngettext, N, library and require.
If expr is a character then gettextify tries first to open a file with the name. If this fails then it wil be assumed that expr contains valid R code.

gettextify ('x<-"a"')
gettextify (system.file(package='gettext', 'shiny', 'app1', 'app.R'))
gettextify (parse(system.file(package='gettext', 'shiny', 'app1', 'app.R')))

Appends a warning to the library-internal translation environment.

msgWarning('duplicate entry')

Returns a translated string from the untranslated string id2. An abbreviated form is N since R does not support _ as unary operator.

ngettext("I saw one duck", "I saw \%.0f ducks", 1)
sprintf(ngettext("I saw \%0.f duck", "I saw \%.0f ducks", 3), 3) # no translation at all
sprintf(N("I saw a duck", "I saw \%.0f ducks", 3), 3)

Converts a plural from from text to list with the input text, nplurals value and a R function plural(n) which computes the plural index from n. \itemize{ \item Note 1: The index is increased by one since R starts with x[1] and C with x[0] \item Note 2: Only a subset of C symbols are supported based on the test cases: (, ), \%, <, >, >=, <=, &&, ||, ?:, =, and ;. }

# Belarusian plural form
p <- paste0('nplurals=3;',
     'plural=(n\%10==1 && n\%100!=11 ? 0 : n\%10>=2 && n\%10<=4 && (n\%100<10 || n\%100>=20) ? 1 : 2);')
l <- plural2R(p)
l$nplurals
l$plural(0:100)

Prints all warning messages for the translation object.

printWarnings()

Reads one or more PO file into the library internal translation object. If file has been created with [language()] then several files with different domains and languages can be read at once.

\dontrun{
readPofile('test_de.po', lang='de')
readPofile(languageFiles('test_de.po'))
}

\itemize{ \item saveTranslation saves the library-internal translation environment as an RDS file, for details see [base::saveRDS()]. \item readTranslation restores the library-internal translation environment from an RDS file, for details see [base::readRDS()]. \item cleanTranslation deletes in all domains and languages the translations in the library-internal translation environment. }

\dontrun{
saveTranslation("translation.RDS")
cleanTranslation()
readTranslation("translation.RDS")
}

Creates a POT file from text extracted with [xgettext()].

txt <- xgettext(parse(system.file('app1', 'app.R', package='gettext')))
\dontrun{
writePotfile(txt, 'myproject.pot')
}

Extracts all text constants from R program including gettext calls.

xgettext(parse(system.file('app1', 'app.R', package='gettext')))
xgettext(parse(system.file('app2', 'app.R', package='gettext')))

txt <- xgettext(parse(system.file('shiny', 'app1', 'app.R', package='gettext')))
txt