Class: AnsiSys::Lexer

Inherits:
Object
  • Object
show all
Defined in:
lib/ansisys.rb

Constant Summary collapse

PARAMETER_AND_LETTER =

Control Sequence Introducer and following code

/\A([\d;]*)([[:alpha:]])/o
CODE_EQUIVALENT = 
{
	"\r" => ['B'],
	"\n" => ['E'],
}

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(csis = ["\x1b["]) ⇒ Lexer

csis is an Array of Code Sequence Introducers which can be e[, x9B, or both



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# File 'lib/ansisys.rb', line 46

def initialize(csis = ["\x1b["])	# CSI can also be "\x9B"
	@code_start_re = Regexp.union(*(CODE_EQUIVALENT.keys + csis))
	@buffer = ''
end

Instance Attribute Details

#buffer ⇒ Object (readonly)

Returns the value of attribute buffer.



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# File 'lib/ansisys.rb', line 42

def buffer
  @buffer
end

Instance Method Details

#lex! ⇒ Object

returns array of tokens while deleting the tokenized part from buffer



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# File 'lib/ansisys.rb', line 57

def lex!
	r = Array.new
	@buffer.gsub!(/(?:\r\n|\n\r)/, "\n")
	while @code_start_re =~ @buffer
		r << [:string, $`] unless $`.empty?
		if CODE_EQUIVALENT.has_key?($&)
			CODE_EQUIVALENT[$&].each do |c|
				r << [:code, c]
			end
			@buffer = $'
		else
			csi = $&
			residual = $'
			if PARAMETER_AND_LETTER =~ residual
				r << [:code, $&]
				@buffer = $'
			else
				@buffer = csi + residual
				return r
			end
		end
	end
	r << [:string, @buffer] unless @buffer.empty?
	@buffer = ''
	return r
end

#push(string) ⇒ Object

add the String (clear text with some or no escape sequences) to buffer



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# File 'lib/ansisys.rb', line 52

def push(string)
	@buffer += string
end