1 # heavily based on Masao Mutoh's gettext String interpolation extension
2 # http://github.com/mutoh/gettext/blob/f6566738b981fe0952548c421042ad1e0cdfb31e/lib/gettext/core_ext/string.rb
5 INTERPOLATION_PATTERN = Regexp.union(
7 /%\{(\w+)\}/, # matches placeholders like "%{foo}"
8 /%<(\w+)>(.*?\d*\.?\d*[bBdiouxXeEfgGcps])/ # matches placeholders like "%<foo>.d"
12 def interpolate(string, values)
13 raise ReservedInterpolationKey.new($1.to_sym, string) if string =~ RESERVED_KEYS_PATTERN
14 raise ArgumentError.new('Interpolation values must be a Hash.') unless values.kind_of?(Hash)
15 interpolate_hash(string, values)
18 def interpolate_hash(string, values)
19 string.gsub(INTERPOLATION_PATTERN) do |match|
23 key = ($1 || $2).to_sym
24 value = values.key?(key) ? values[key] : raise(MissingInterpolationArgument.new(values, string))
25 value = value.call(values) if value.respond_to?(:call)
26 $3 ? sprintf("%#{$3}", value) : value