module Protocol::HTTP::Header::QuotedString

def self.quote(value, force = false)

@raises [ArgumentError] if the value contains invalid characters like control characters or newlines.

Quote a string for HTTP header values if required. 
def self.quote(value, force = false)
	# Check if quoting is required:
	if value =~ QUOTES_REQUIRED or force
		"\"#{value.gsub(/["\\]/, '\\\\\0')}\""
	else
		value
	end
end