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instance method

GetoptLong#error_message

error_message

# File tmp/rubies/ruby-3.1.3/lib/getoptlong.rb, line 415
def error_message
  return @error_message
end

Return the appropriate error message in POSIX-defined format. If no error has occurred, returns nil.

See also #each_option #get #each #get_option also in 3.3 · 3.2 · 3.0