Class: XRT::Parser

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

Instance Method Summary collapse

Constructor Details

#initialize(source = '') ⇒ Parser

Returns a new instance of Parser.



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# File 'lib/xrt/parser.rb', line 5

def initialize(source='')
  @source = source
end

Instance Method Details

#document ⇒ Object 



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# File 'lib/xrt/parser.rb', line 9

def document
  doc = XRT::Statement::Document.new

  tokenized = self.tokens

  parse_contents(tokenized, doc)
  doc
end

#parse_contents(tokenized, node) ⇒ Object

read tokens from tokenized tokens push contents to (container) node returns parsed container node return when tokenized is empty, or node is closed



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# File 'lib/xrt/parser.rb', line 22

def parse_contents(tokenized, node)
  while tokenized.length > 0
    statement = XRT::Statement::Factory.new_from_content(tokenized.shift)

    case statement
    when XRT::Statement::Tag
      parse_contents(tokenized, statement)
      if statement.tag_opening?
        statement = XRT::Statement::TagPair.new(statement)
        parse_contents(tokenized, statement)
        node << statement
        next
      elsif statement.tag_closing?
        statement = XRT::Statement::TagPairEnd.new(statement)
        node << statement
        break
      else
        node << statement
        next
      end
    end

    case statement
    when XRT::Statement::Block
      parse_contents(tokenized, statement)
      node << statement
    when XRT::Statement::End
      node << statement
      break
    else
      node << statement
    end
  end

  node
end

#read_directive(source) ⇒ Object 



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# File 'lib/xrt/parser.rb', line 93

def read_directive source
  return nil unless source[0...2] == '[%'

  buffer = ''
  while source[0...2] != '%]'
    buffer << source.slice!(0)
  end
  buffer << source.slice!(0, 2)
  buffer
end

#read_tag_end(source) ⇒ Object 



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# File 'lib/xrt/parser.rb', line 128

def read_tag_end source
  return nil unless source[0] == '>'
  source.slice!(0)
end

#read_tag_start(source) ⇒ Object 



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# File 'lib/xrt/parser.rb', line 123

def read_tag_start source
  return nil unless source[0] == '<'
  source.slice!(0)
end

#read_text(source) ⇒ Object 



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# File 'lib/xrt/parser.rb', line 104

def read_text source
  return nil if source[0...2] == '[%'
  return nil if source[0] == '<'
  return nil if source[0] == '>'

  buffer = ''
  while true
    return buffer if source[0...2] == '[%'
    return buffer if source[0] == '<'
    return buffer if source[0] == '>'
    break if source.length < 2
    buffer << source.slice!(0)
  end

  buffer << source.slice!(0, source.length)

  buffer
end

#split_whitespace(text) ⇒ Object 



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# File 'lib/xrt/parser.rb', line 80

def split_whitespace(text)
  prefix, suffix=nil
  text.sub!(/\A(\s+)/) {|matched|
    prefix = matched
    ''
  }
  text.sub!(/(\s+)\Z/) {|matched|
    suffix = matched
    ''
  }
  [prefix, text, suffix].compact.delete_if{|s| s.empty?}
end

#tokens ⇒ Object 



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# File 'lib/xrt/parser.rb', line 59

def tokens
  reading = @source.dup
  result = []

  while reading.length > 0
    if got = read_directive(reading)
      result << got
    elsif got = read_tag_start(reading)
      result << got
    elsif got = read_tag_end(reading)
      result << got
    elsif got = read_text(reading)
      result.concat(split_whitespace(got))
    else
      raise "failed to parse #{@source}"
    end
  end

  result
end