gettext: javascript-format
15.3.6 JavaScript Format Strings
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Although JavaScript specification itself does not define any format
strings, many JavaScript implementations provide printf-like functions.
‘xgettext’ understands a set of common format strings used in popular
JavaScript implementations including Gjs, Seed, and Node.JS. In such a
format string, a directive starts with ‘%’ and is finished by a
specifier: ‘%’ denotes a literal percent sign, ‘c’ denotes a character,
‘s’ denotes a string, ‘b’, ‘d’, ‘o’, ‘x’, ‘X’ denote an integer, ‘f’
denotes floating-point number, ‘j’ denotes a JSON object.