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class CharacterSet
module Parser
module_function
def codepoints_from_enumerable(object)
raise ArgumentError, 'pass an Enumerable' unless object.respond_to?(:each)
# Use #each to check first element (only this works for all Enumerables)
object.each do |el| # rubocop:disable Lint/UnreachableLoop
if el.is_a?(Integer) && el >= 0 && el < 0x110000
return object
elsif el.is_a?(String) && el.length == 1
return object.to_a.join.encode('utf-8').codepoints
end
raise ArgumentError, "#{el.inspect} is not valid as a codepoint"
end
end
def codepoints_from_bracket_expression(string)
raise ArgumentError, 'pass a String' unless string.is_a?(String)
raise ArgumentError, 'advanced syntax' if string =~ /\\[^uUx]|[^\\]\[|&&/
content = strip_brackets(string)
literal_content = eval_escapes(content)
prev_chr = nil
in_range = false
literal_content.each_char.map do |chr|
if chr == '-' && prev_chr && prev_chr != '\\' && prev_chr != '-'
in_range = true
nil
else
result = in_range ? ((prev_chr.ord + 1)..(chr.ord)).to_a : chr.ord
in_range = false
prev_chr = chr
result
end
end.compact.flatten
end
def strip_brackets(string)
string[/\A\[\^?(.*)\]\z/, 1] || string.dup
end
def eval_escapes(string)
string.gsub(/\\U(\h{8})|\\u(\h{4})|U\+(\h+)|\\x(\h{2})|\\u\{(\h+)\}/) do
($1 || $2 || $3 || $4 || $5).to_i(16).chr('utf-8')
end
end
end
end
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