Class: Bijou::Parser

Inherits:
Object
  • Object
show all
Includes:
Parse
Defined in:
lib/bijou/parser.rb

Overview

The Bijou parser is a bi-modal top-down LL(1) parser. It is bi-modal in that it uses two lexers. One for markup and the other for Bijou tags.

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize ⇒ Parser

Returns a new instance of Parser.



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# File 'lib/bijou/parser.rb', line 43

def initialize
  @debug = false
  # REVIEW: Make this an option      
  @strip = true
  @strippingTag = false

#    @debug = true
  @diagnostics = nil
  @input = nil
  @backend = nil
  detach_file
end

Instance Attribute Details

#diagnostics ⇒ Object (readonly)

Returns the value of attribute diagnostics.



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# File 'lib/bijou/parser.rb', line 41

def diagnostics
  @diagnostics
end

#filename ⇒ Object (readonly)

The filename is written to line marker comments in the output.



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# File 'lib/bijou/parser.rb', line 39

def filename
  @filename
end

Instance Method Details

#assert(c) ⇒ Object 



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# File 'lib/bijou/parser.rb', line 125

def assert(c)
  if (!c)
    error("assert failed on line " + @lexer.line.to_s)
  end
end

#attach_file(file, filename) ⇒ Object 



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# File 'lib/bijou/parser.rb', line 73

def attach_file(file, filename)
  @filename = filename

  @diagnostics = Diagnostics.new

  trace = false
  use_markers = true # The Perl-oriented '#line' marker, for stack traces.

  @input = LexerInput.new(file, @diagnostics)
  @backend = Backend.new(@diagnostics, trace, use_markers)

  @topLexer = TextLexer.new(@input)
  @tagLexer = TagLexer.new(@input)

  @lexer = @topLexer 
  @parsingArgs = false
  @namedSection = nil
end

#debug(str) ⇒ Object 



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# File 'lib/bijou/parser.rb', line 121

def debug(str)
  puts str if @debug
end

#debug_(str) ⇒ Object 



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# File 'lib/bijou/parser.rb', line 117

def debug_(str)
  print str if @debug
end

#detach_file ⇒ Object 



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# File 'lib/bijou/parser.rb', line 56

def detach_file
  @filename = ''

  # We keep the diagnostics and the backend
  # @diagnostics
  # @backend

  @input = nil

  @topLexer = nil
  @tagLexer = nil

  @lexer = nil
  @parsingArgs = false
  @namedSection = nil
end

#diagnostic(m, l, c) ⇒ Object 



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# File 'lib/bijou/parser.rb', line 92

def diagnostic(m, l, c)
  if !l; l = @lexer.line; end
  if !c; c = @lexer.column; end
  m.at(l, c)
  m
end

#eatArgumentWhitespace ⇒ Object 



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# File 'lib/bijou/parser.rb', line 167

def eatArgumentWhitespace()
  lineComment = false

  while tok = @lexer.next_token

    if lineComment
      if tok == Token::Char && @lexer.text == "\n"
        # warning("eat arg crlf")
        lineComment = false
        next
      else
        # Eat comments
        next
      end
    end

    if tok == Token::Char
      str = @lexer.text
      
      if str == '#'
        # warning("eat arg comment")
        lineComment = true
      elsif str == "\n"
        # warning("eat arg crlf")
        # lineComment = false
      elsif @lexer.text =~ /\s/
        # Eat whitespace
      else # non-whitespace
        # This should be an identifier
        # warning("eat arg ws 1 #{@lexer.text}")
        @lexer.pop_token
        return true
      end
    else
      # warning("eat arg ws 3 #{@lexer.text} #{tok}")
      @lexer.pop_token
      return true
    end
  end

  # EOF
  return false
end

#eatLineWhitespace ⇒ Object 



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# File 'lib/bijou/parser.rb', line 157

def eatLineWhitespace()
  while tok = @lexer.next_token
    if tok != Token::Char || @lexer.text !~ /\s/ || @lexer.text == '\n'
      @lexer.pop_token
      return true
    end
  end
  return nil
end

#eatWhitespace ⇒ Object 



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# File 'lib/bijou/parser.rb', line 147

def eatWhitespace()
  while tok = @lexer.next_token
    if tok != Token::Char || @lexer.text !~ /\s/
      @lexer.pop_token
      return true
    end
  end
  return nil
end

#error(s, line = nil, column = nil) ⇒ Object 



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# File 'lib/bijou/parser.rb', line 111

def error(s, line=nil, column=nil)
  m = Error.new
  m << s
  @input.diagnostics.add_error(diagnostic(m, line, column))
end

#expectChar(ch, msg = '') ⇒ Object 



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# File 'lib/bijou/parser.rb', line 238

def expectChar(ch, msg='')
  if tok = @lexer.next_token
    if tok == Token::Char
      if @lexer.text == '='
        return true
      end
    end
    error("expected #{ch}#{msg}")
  else
    error("expected #{ch}#{msg} at end of file")
  end
  false
end

#findTagClose(openToken, closeToken) ⇒ Object 



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# File 'lib/bijou/parser.rb', line 252

def findTagClose(openToken, closeToken)
  while tok = @lexer.next_token
    if tok == Token::TagClose
      tagClose = @lexer.text
      if tagClose != closeToken
        error("expected '#{closeToken}' to close '#{openToken}' tag")
      end
      return
    end
  end
  error("expected close tag for '#{openToken}' at end of file")
end

#message(s, line = nil, column = nil) ⇒ Object 



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# File 'lib/bijou/parser.rb', line 99

def message(s, line=nil, column=nil)
  m = Message.new
  m << s
  @input.diagnostics.add_message(diagnostic(m, line, column))
end

#parse(component, file, filename = '') ⇒ Object 



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# File 'lib/bijou/parser.rb', line 919

def parse(component, file, filename='')
  if !file.respond_to?(:read)
    if file.respond_to?(:to_s)
      # This is a fallback; use StringIO for better performance.
      file = StringIO.new(file.dup)
    else
      raise ArgumentError, "must be a file or a string"
    end
  end

  parse_file(component, file, filename='')

  render(component)
end

#parse_file(component, file, filename = '') ⇒ Object

The main top-level parsing loop looks for the special Bijou start tags, dispatches to the specialized parsing routines, and manages the lexer switching process.



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# File 'lib/bijou/parser.rb', line 943

def parse_file(component, file, filename='')
  #
  # Initialize parser members.
  #
  attach_file(file, filename)

  #
  # Main parsing loop
  #
  source_line = @lexer.line
  buffer = ''
  while tok = @lexer.next_token
    if tok == Token::Char
      buffer << @lexer.text
    elsif tok == Token::TagOpen
      if @strip && @strippingTag
        buffer = stripLeader(buffer)
      end
      @strippingTag = false

      @backend.markup_section(buffer, @filename, source_line)
      buffer = ''

      # NOTE: Care must be taked in the implementation of the parsing 
      # routines because the lookahead token may buffer characters from
      # the input stream. If this causes problems, then the lexer should
      # should flush (push) the lookahead characters.
      tagStart = @lexer.text

      @lexer = @tagLexer
      parseTag(tagStart)
      @lexer = @topLexer

      if @parsingArgs
        @topLexer.tokenize_arguments = true
        parseArgsSection
        @topLexer.tokenize_arguments = false
      end

      source_line = @lexer.line
    else
      # puts "Token: " + @lexer.text
      error("Unexpected token #{@lexer.text}")
    end
  end

  if @parsingArgs
    error("no end tag for args section at end of file")
    @parsingArgs = false
  end

  # Final section
  if !buffer.empty?
    # The last blank lines are stripped
    if @strip
      buffer = stripTrailer(buffer)
    end

    @backend.markup_section(buffer, @filename, source_line)
    buffer = ''
  end

  # print "Chars: " + @input.character.to_s
  detach_file
end

#parse_string(component, text) ⇒ Object 



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# File 'lib/bijou/parser.rb', line 934

def parse_string(component, text)
  file = StringIO.new(text.dup)
  parse_file(component, file)
  file.close
end

#parseArgsSection ⇒ Object 



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# File 'lib/bijou/parser.rb', line 770

def parseArgsSection
#    @lexer.start(tagStart, TagType::Call)

  debug("parseArgsSection")

  start_line = @lexer.line
  start_column = @lexer.column

  loop do
    lineComment = false

    # warning("before whitespace")
    eatArgumentWhitespace
    # warning("after whitespace")

    tok = @lexer.next_token
    if tok == Token::TagOpen
      # Normal argument end case.
      @lexer.pop_token
      return
    else
      @lexer.pop_token
    end

    # warning('after whitespace')
    argName = parseIdentifier
    if argName.empty?
      error('expected argument identifier')
    end

    # warning("after identifier '#{argName}'")
    # Eat whitespace only up until a linefeed.
    eatLineWhitespace

    # NOTE: We require that any value specified be a single-line expression.
    # Although the backend may be able to render a multi-line assignment,
    # it is not possible to distinguish between a lone identifier and an
    # expression continuation. (In addition, our lexer does not tokenize 
    # identifiers, [the parser does], which would preclude a single-token 
    # lookahead. This would only be useful if the assignment operator were 
    # required.)

    tok = @lexer.next_token
    if tok == Token::TagOpen
      # warning('args end 2')
      # The last argument has no value.
      @backend.add_argument(argName, nil, @filename,
                            @lexer.line, @lexer.column)
      @lexer.pop_token
      return
    elsif tok == Token::Operator && @lexer.text == '=>'
      # warning('=>')

      argValue = ''

      while tok = @lexer.next_token
        if tok == Token::Char
          str = @lexer.text
          if str == '#' || str == "\n"
            @lexer.pop_token

            argValue = argValue.strip
            if argValue.empty?
              error('An argument assignment has no value')
            else
              # warning "comment/eol #{argName} => #{argValue}"
              @backend.add_argument(argName, argValue, @filename,
                                    @lexer.line, @lexer.column)
            end

            argName = nil
            argValue = ''
            break
          else
            argValue << str
          end
        elsif tok == Token::String
          argValue << @lexer.text
        elsif tok == Token::TagOpen
          # Syntax error of the form:
          # arg-name => </%args>
          error('An argument assignment has no value')
          @lexer.pop_token
          return
        end
      end
    elsif tok == Token::Char && (@lexer.text == '#' || @lexer.text =~ /\w/)
      # warning("comment or new identifier")
      @backend.add_argument(argName, nil, @filename,
                            @lexer.line, @lexer.column)
      @lexer.pop_token
    else
      error("unexpected token '#{@lexer.text}' after argument '#{argName}'")
      @lexer.pop_token

      # Wait for the end token
      while tok = @lexer.next_token
        if tok == Token::TagOpen
          @lexer.pop_token
          return
        end
      end

      return
    end
  end # while true

end

#parseCallArgList ⇒ Object 



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# File 'lib/bijou/parser.rb', line 536

def parseCallArgList
  debug("parseCallArgList")

  start_line = @lexer.line
  start_column = @lexer.column

  arg_list = []
  arg_name = nil
  arg_value = nil

  loop do
    eatWhitespace
    arg_name = parseFilename
    if !arg_name || arg_name.empty?
      error("Argument name expected")
      return nil
    end

    eatWhitespace
    if tok = @lexer.next_token
      if tok == Token::Operator && @lexer.text == '=>'
        arg_value = parseCallArgValue
        debug "arg_value #{arg_value}"
        if arg_value && !arg_value.empty?
#            if arg_list.has_key?(arg_name)
#              warning("argument '#{arg_name}' duplicated")
#            end

          arg_list.push [arg_name, arg_value]

          arg_name = nil
          arg_value = nil
        else
          error("empty argument value after assignment operator '=>'")
          return nil
        end
        # look for , or %>
      else
        error("expected assignment operator '=>' after argument identifier #{@lexer.text}")
        @lexer.pop_token
        return nil
      end
    else
      error("unclosed call tag")
      return nil
    end

    eatWhitespace
    if tok = @lexer.next_token
      if tok == Token::TagClose
        tagClose = @lexer.text
        if tagClose == '&>'
          # End of successful parse
          @lexer.pop_token
          return arg_list
        else
          error("expected '&>' to close call tag at (#{start_line}, #{start_column})")
          @lexer.pop_token
          return nil
        end
      elsif tok != Token::Char || @lexer.text != ','
        error("unexpected token '#{@lexer.text}' after argument value", start_line, start_column)
        @lexer.pop_token
        # End of argument list
        return nil
      end
    end

  end
end

#parseCallArgValue ⇒ Object

Parse until ‘,’ or ‘&>’ is found.



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# File 'lib/bijou/parser.rb', line 500

def parseCallArgValue
  result = ''

  start_line = @lexer.line
  start_column = @lexer.column

  while tok = @lexer.next_token
    if tok == Token::Char
      if @lexer.text == ','
        @lexer.pop_token
        return result.strip
      end
      result << @lexer.text
    elsif tok == Token::String
      result << @lexer.text
    elsif tok == Token::Operator
      # We have to include this in case it is within another hash.
      result << @lexer.text
    elsif tok == Token::TagClose
      tagClose = @lexer.text
      if tagClose != '&>'
        error("expected '&>' to close call tag at (#{start_line}, #{start_column})")
      end

      @lexer.pop_token
      return result.strip
    else
      error("unexpected token '#{@lexer.text}'", start_line, start_column)
      return nil
    end
  end

  error("unclosed call tag after assignment '=>'")
  return nil
end

#parseCallTag(tagStart) ⇒ Object

Parses a tag of the form <& name { arg-list } &> where arg-list is an optional Ruby hash.



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# File 'lib/bijou/parser.rb', line 609

def parseCallTag(tagStart)
  @lexer.start(tagStart, TagType::Call)

  debug("parseCallTag #{tagStart}")

  start_line = @lexer.line
  start_column = @lexer.column

  # Is this an indirect call?
  indirect = false

  if tok = @lexer.next_token
    if tok == Token::Char && @lexer.text == '='
      indirect = true
    else
      @lexer.pop_token
    end
  end

  # REVIEW: Should we allow indirect calls with @member syntax?
  eatWhitespace
  callIdentifier = parseFilename
  if !callIdentifier || callIdentifier.empty?
    error("Identifier expected in call tag")
  end

  arg_list = nil

  eatWhitespace
  if tok = @lexer.next_token
    if tok == Token::Char
      if @lexer.text == ','
        @lexer.tokenize_arguments = true
        arg_list = parseCallArgList
        @lexer.tokenize_arguments = false

        findTagClose('<&', '&>')

        if arg_list
          # Send to the backend
          @backend.call_tag(callIdentifier, arg_list, indirect, 
                            @filename, start_line)
        end

        return
      else
        error("unexpected token '#{@lexer.text}' after call identifier", start_line, start_column)

        findTagClose('<&', '&>')
        return
      end
    else
      tagClose = @lexer.text
      if tagClose != '&>'
        error("expected '&>' to close call tag at (#{start_line}, #{start_column})")
      end

      result = {}

      # Send to the backend
      @backend.call_tag(callIdentifier, result, indirect, 
                        @filename, start_line)
      return
    end
  end

  error("unclosed call tag")
  return


  while tok = @lexer.next_token
    if tok == Token::Char
      result << @lexer.text
    elsif tok == Token::String
      result << @lexer.text
    elsif tok == Token::TagClose
      tagClose = @lexer.text
      # BUGBUG <& X %> doesn't fire.
      if tagClose != '&>'
        error("expected '&>' to close call tag at (#{start_line}, #{start_column})")
      end

      if result.strip.empty?
        result = '{}'
      end

      # Send to the backend
      @backend.call_tag(callIdentifier, result, indirect, 
                        @filename, start_line)
      return
    else
      error("unexpected tag token '#{@lexer.text}'", start_line, start_column)
    end
  end

  error("unclosed call tag")
end

#parseCharSequence(re) ⇒ Object 



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# File 'lib/bijou/parser.rb', line 211

def parseCharSequence(re)
  debug_("parseCharSequence: ")
  name = ''

  while tok = @lexer.next_token
    text = @lexer.text
    if tok == Token::Char && text =~ re
      name << text
    else
      @lexer.pop_token
      debug(name)
      return name
    end
  end

  debug(name + "<eof>")
  return name
end

#parseDirectiveTag(tagStart) ⇒ Object

Parses tags of the form <%! name1=“value1” name2 = “value2” … %>, which control compile time and runtime behavior. These tags are usually placed near the top of the file.



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# File 'lib/bijou/parser.rb', line 710

def parseDirectiveTag(tagStart)
  @lexer.start(tagStart, TagType::Directive)

  start_line = @lexer.line
  start_column = @lexer.column

  here = 'in <%! directive'

  errors = 0
  directives = {}

  while true
    eatWhitespace

    if tok = @lexer.next_token
      if tok == Token::TagClose
        if @lexer.text == '%>'
          if directives.length > 0
            # Send to the backend
            @backend.directive_tag(directives, start_line, start_column)

            # Whitespace following this tag may be stripped
            @strippingTag = true
          end
        else
          error("expected '%>' to close directive '<%!' tag")
        end
        return # Main loop exit
      else
        @lexer.pop_token
      end
    end
    
    identifierName = parseIdentifier
    if identifierName.empty?
      error("expected identifier in directive")
    end

    eatWhitespace
    
    if !expectChar('=', " after literal #{here}")
      findTagClose('<%!', '%>')
      return
    end
    
    eatWhitespace
    
    if tok = @lexer.next_token
      if tok == Token::String
        directives[identifierName] = @lexer.text
      else
        error("unexpected token #{@lexer.text} after assignment #{here}")
        findTagClose('<%!', '%>')
        return
      end
    end
  end

end

#parseFilename ⇒ Object 



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# File 'lib/bijou/parser.rb', line 234

def parseFilename
  parseCharSequence(/[\\\/\w\.]/)
end

#parseIdentifier ⇒ Object 



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# File 'lib/bijou/parser.rb', line 230

def parseIdentifier
  parseCharSequence(/\w/)
end

#parseInlineTag(tagStart) ⇒ Object

Parses tags of the form <% … %>, which may contain any valid Ruby statements. The contents of the inline tag are evaluated at runtime during the render phase. The puts and print methods may be used to render to the output stream.



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# File 'lib/bijou/parser.rb', line 408

def parseInlineTag(tagStart)
  @lexer.start(tagStart, TagType::Inline)

  debug("parseInlineTag #{tagStart}")

  # BUGBUG: Turn off quote handling in comments.
  # BUGBUG: We may want to turn of string parsing here (at the cost of not
  # handling quoted close tokens).
  start_line = @lexer.line
  start_column = @lexer.column

  result = ''

  while tok = @lexer.next_token
    if tok == Token::Char
      result << @lexer.text
    elsif tok == Token::String
      result << @lexer.text
    elsif tok == Token::TagClose
      tagClose = @lexer.text
      if tagClose != '%>'
        error("expected '%>' to close inline '<%' tag at (#{start_line}, #{start_column})")
      end

      debug("#{result}%>")

      # Send to the backend
      @backend.inline_tag(result, @filename, start_line)
      return
    else
      error("unexpected tag token '#{@lexer.text}'", start_line, start_column)
    end
  end

  if @lexer.line != start_line
    error("unclosed inline tag (was this supposed to be a named tag?)", 
          start_line, start_column)
  else
    error("unclosed inline tag (was this supposed to be a named tag?)")
  end
end

#parseNamedTag(tagStart) ⇒ Object

Parses named tags of the form <%name> and </%name>. Due to the ambiguity that the start token causes between inline tags and named tags, this routine performs a lookahead and dispatches to the correct parsing routine.



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# File 'lib/bijou/parser.rb', line 294

def parseNamedTag(tagStart)
  debug("parseNamedTag #{tagStart}")
  nameIdentifier = nil

  if tagStart == '<%'
    tagName = parseTagName
    case tagName
    when 'init'
      @namedSection = tagName

    when 'fini'
      @namedSection = tagName

    when 'method'
      @namedSection = tagName

    when 'args'
      if @parsingArgs
        error("args may not be nested within other args sections")
      end
      @parsingArgs = true
    else
      @lexer.start(tagStart, TagType::Inline)
      parseInlineTag(tagStart)
      return
    end

    @lexer.start(tagStart, TagType::Named)

    start_line = @lexer.line
    start_column = @lexer.column

    if tagName == 'method'
      # <%method name...
      #         ^
      debug_("ws(")
      eatWhitespace
      debug(")")

      nameIdentifier = parseIdentifier
      if nameIdentifier.empty?
        error("expected method name")
      end
    end
  else
    assert(tagStart == '</%')
    @lexer.start(tagStart, TagType::Named)

    start_line = @lexer.line
    start_column = @lexer.column

    # Whitespace following this tag may be stripped
    @strippingTag = true

    tagName = parseTagName
    if tagName
      case tagName
      when 'init'
      when 'fini'
      when 'args'
        @parsingArgs = false
      when 'method'
      else
        error("section close type '</%#{tagName}' is unrecognized")
      end

      @namedSection = nil
    else
      error("expected name after '</%'")
    end
  end

  # <%name ...
  #       ^
  debug_("eatws(")
  eatWhitespace
  debug(")")

  #
  # NOTE: The token may be a Char, even though it's for a tag close.
  #
  # This is a special case for when a tag name goes against the close
  # tag token (e.g., <%init>). Because of the ambiguity caused by the two 
  # different tag types opening with the same token, we must lookahead while
  # we parse the identifier. Since we haven't switched into TagType::Named
  # yet, '>' is regarded as a Char instead of a TagClose.
  # 

  tok = @lexer.next_token
  tagClose = @lexer.text

  if tok == Token::TagClose || tok == Token::Char
    if tagClose == '>'
      # Send to the backend
      if tagStart == '<%'
        @backend.named_start_tag(tagName, nameIdentifier, 
                                 start_line, start_column)
      else
        assert(tagStart == '</%')
        @backend.named_end_tag(tagName)
      end
    else
      error("expected '>' to close #{tagName} tag")
    end
  else
    error("unexpected token '#{@lexer.text}' in " +
          "#{tagName} tag", start_line, start_column)
  end
end

#parseOutputFlags ⇒ Object

Returns a two item array as a result, the string following the pipe operator ‘|’ and a hash containing filters, if found.



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# File 'lib/bijou/parser.rb', line 267

def parseOutputFlags
  result = ''
  filters = []
  while tok = @lexer.next_token
    if tok == Token::Char
      if @lexer.text =~ /[a-z]/
        filters.push @lexer.text
      elsif @lexer.text !~ /\s/
        @lexer.pop_token
        return [result, []]
      end
      result << @lexer.text
    elsif tok == Token::TagClose
      @lexer.pop_token
      return [result, filters]
    else
      @lexer.pop_token
      return [result, []]
    end
  end
  error("expected '%>' to close output tag '<%=' at end of file")
  return [result, []]
end

#parseOutputTag(tagStart) ⇒ Object

Parses tags of the form <%= … %> where the contents may be any valid Ruby expression. This expression is evaluated at runtime in a string context and the results are rendered to the output stream.



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# File 'lib/bijou/parser.rb', line 453

def parseOutputTag(tagStart)
  @lexer.start(tagStart, TagType::Output)

  debug("parseOutputTag #{tagStart}")

  start_line = @lexer.line
  start_column = @lexer.column

  result = ''
  filters = nil

  while tok = @lexer.next_token
    if tok == Token::Char
      if @lexer.text == '|'
        # Returns an array containing [string, array]
        flags = parseOutputFlags
        if flags[1].length > 0
          # Flags were found.
          filters = flags[1]
        else
          # False alarm
          result << '|' + flags[0]
        end
      else
        result << @lexer.text
      end
    elsif tok == Token::String
      result << @lexer.text
    elsif tok == Token::TagClose
      tagClose = @lexer.text
      if tagClose != '%>'
        error("expected '%>' to close output '<%=' tag")
      end

      # Send to the backend
      @backend.output_tag(result, filters, @filename, start_line)
      return
    else
      error("invalid output tag syntax", start_line, start_column)
      error("unexpected token '#{@lexer.text}'")
    end
  end

  error("unclosed output tag")
end

#parseTag(tagStart) ⇒ Object

This routine handles the non-markup tags that are meaningful to the Bijou processor. It dispatches to the specific tag handlers. Parsing is done with the specialized tag lexer. Normal markup is parsed using a lexer that only recognizes Bijou tag open tokens. This bi-modal system allows us to ignore the complex parsing that would be required to handle HTML, scripts, style sheets, etc.



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# File 'lib/bijou/parser.rb', line 885

def parseTag(tagStart)
  tagName = nil

  @backend.tag_open(tagStart)

  case tagStart
  when '<%';
    # This handler will determine whether it's named or inline.
    parseNamedTag(tagStart)
    return
  when '<%='
    parseOutputTag(tagStart)
    return
  when '<&';
    parseCallTag(tagStart)
    return
  when '</%';
    # This handler will determine whether it's named or inline.
    parseNamedTag(tagStart)
    return
  when '<%!'
    parseDirectiveTag(tagStart)
    return
  else;
    raise "unexpected tag type #{tagStart}"
  end
end

#parseTagName ⇒ Object 



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# File 'lib/bijou/parser.rb', line 131

def parseTagName
  debug_("parseTagName: ")

  # If the first character isn't a word character, return nil
  tag = ''
  while tok = @lexer.next_token
    if tok != Token::Char || /\w/ !~ @lexer.text 
      @lexer.pop_token
      debug(tag)
      return tag
    end
    tag << @lexer.text
  end
  debug(tag + "<eof>")
end

#render(component, source_filename = nil, cache_filename = nil, base = nil, require_list = nil) ⇒ Object 



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# File 'lib/bijou/parser.rb', line 913

def render(component, source_filename=nil, cache_filename=nil, 
           base=nil, require_list=nil)
  @backend.render(component, source_filename, cache_filename, 
                  base, require_list)
end

#stripLeader(buffer) ⇒ Object

Whitespace formatting helper that removes a single leading blank line when preceded by a tag.



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# File 'lib/bijou/parser.rb', line 1011

def stripLeader(buffer)
  if buffer =~ /\A\s*?\n(.*)\Z/m
    return $1
  end
  return buffer
end

#stripTrailer(buffer) ⇒ Object

Whitespace formatting helper that removes any whitespace at the end of a component.



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# File 'lib/bijou/parser.rb', line 1020

def stripTrailer(buffer)
  if buffer =~ /\A(.*?)\s*\Z/m
    return $1
  end
  return buffer
end

#warning(s, line = nil, column = nil) ⇒ Object 



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# File 'lib/bijou/parser.rb', line 105

def warning(s, line=nil, column=nil)
  m = Warning.new
  m << s
  @input.diagnostics.add_warning(diagnostic(m, line, column))
end