Class: Utopia::XNode::Scanner

Inherits:
StringScanner
  • Object
show all
Defined in:
lib/utopia/xnode/scanner.rb

Constant Summary collapse

CDATA = 
/[^<]+/m
ATTRIBUTE_NAME =

Parse an attribute in the form of key=“value” or key.

/\s*([^\s=\/>]+)/um
ATTRIBUTE_VALUE = 
/=((['"])(.*?)\2)/um

Instance Method Summary collapse

Constructor Details

#initialize(callback, string) ⇒ Scanner

Returns a new instance of Scanner.



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# File 'lib/utopia/xnode/scanner.rb', line 33

def initialize(callback, string)
	@callback = callback
	super(string)
end

Instance Method Details

#calculate_line_number(at = pos) ⇒ Object 



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# File 'lib/utopia/xnode/scanner.rb', line 38

def calculate_line_number(at = pos)
	line_no = 1
	line_offset = offset = 0
	
	string.lines.each do |line|
		line_offset = offset
		offset += line.size
		
		if offset >= at
			return [line_no, line_offset, at - line_offset, offset, line]
		end
		
		line_no += 1
	end
	
	return nil
end

#parse ⇒ Object 



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# File 'lib/utopia/xnode/scanner.rb', line 56

def parse
	until eos?
		pos = self.pos

		scan_cdata
		scan_tag

		if pos == self.pos
			raise ScanError.new("Scanner didn't move", self)
		end
	end
end

#scan_attributes ⇒ Object 



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# File 'lib/utopia/xnode/scanner.rb', line 91

def scan_attributes
	while scan(ATTRIBUTE_NAME)
		name = self[1]
		if scan(ATTRIBUTE_VALUE)
			@callback.attribute(name, self[3])
		else
			@callback.attribute(name, nil)
		end
	end
end

#scan_cdata ⇒ Object 



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# File 'lib/utopia/xnode/scanner.rb', line 69

def scan_cdata
	if scan(CDATA)
		@callback.cdata(matched)
	end
end

#scan_tag ⇒ Object 



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# File 'lib/utopia/xnode/scanner.rb', line 75

def scan_tag
	if scan(/</)
		if scan(/\//)
			scan_tag_normal(CLOSED_TAG)
		elsif scan(/!\[CDATA\[/)
			scan_tag_cdata
		elsif scan(/!/)
			scan_tag_comment
		elsif scan(/\?/)
			scan_tag_instruction
		else
			scan_tag_normal
		end
	end
end

#scan_tag_cdata ⇒ Object 



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# File 'lib/utopia/xnode/scanner.rb', line 128

def scan_tag_cdata
	if scan_until(/(.*?)\]\]>/m)
		@callback.cdata(self[1].to_html)
	else
		raise ScanError.new("CDATA tag is not closed!", self)
	end
end

#scan_tag_comment ⇒ Object 



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# File 'lib/utopia/xnode/scanner.rb', line 136

def scan_tag_comment
	if scan(/--/)
		if scan_until(/(.*?)-->/m)
			@callback.comment("--" + self[1] + "--")
		else
			raise ScanError.new("Comment is not closed!", self)
		end
	else
		if scan_until(/(.*?)>/)
			@callback.comment(self[1])
		else
			raise ScanError.new("Comment is not closed!", self)
		end
	end
end

#scan_tag_instruction ⇒ Object 



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# File 'lib/utopia/xnode/scanner.rb', line 152

def scan_tag_instruction
	if scan_until(/(.*)\?>/)
		@callback.instruction(self[1])
	end
end

#scan_tag_normal(begin_tag_type = OPENED_TAG) ⇒ Object 



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# File 'lib/utopia/xnode/scanner.rb', line 102

def scan_tag_normal(begin_tag_type = OPENED_TAG)
	if scan(/[^\s\/>]+/)
		@callback.begin_tag(matched, begin_tag_type)
	
		scan(/\s*/)
	
		scan_attributes
	
		scan(/\s*/)
	
		if scan(/\/>/)
			if begin_tag_type == CLOSED_TAG
				raise ScanError.new("Tag cannot be closed at both ends!", self)
			else
				@callback.finish_tag(begin_tag_type, CLOSED_TAG)
			end
		elsif scan(/>/)
			@callback.finish_tag(begin_tag_type, OPENED_TAG)
		else
			raise ScanError.new("Invalid characters in tag!", self)
		end
	else
		raise ScanError.new("Invalid tag!", self)
	end
end