Class: LLIP::AbstractParser

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

Overview

This class hide all the complexity of generating an building a parser. Ater subclassing it, it’s possible to use all the methods defined in AbstractParser::ClassMethods to specify the productions.

Direct Known Subclasses

RegexpParser

Defined Under Namespace

Modules: ClassMethods

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize ⇒ AbstractParser

Returns a new instance of AbstractParser.



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# File 'lib/llip/abstract_parser.rb', line 17

def initialize
  @hash = {}
end

Class Method Details

.inherited(other) ⇒ Object 



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# File 'lib/llip/abstract_parser.rb', line 13

def self.inherited(other)
  other.extend(ClassMethods)
end

Instance Method Details

#[](key) ⇒ Object 



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# File 'lib/llip/abstract_parser.rb', line 31

def [](key)
  @hash[key]
end

#[]=(key, value) ⇒ Object 



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# File 'lib/llip/abstract_parser.rb', line 35

def []=(key,value)
  @hash[key] = value
end

#parse(scanner) ⇒ Object

Parse the token generated from the scanner until it reaches the end. See AbstractScanner to know how to develop a scanner.



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# File 'lib/llip/abstract_parser.rb', line 27

def parse(scanner)
  raise "This method hasn't been compiled yet."
end

#productions ⇒ Object 



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# File 'lib/llip/abstract_parser.rb', line 21

def productions
  self.class.productions
end

#raise(*args) ⇒ Object

It raises a ParserError instead of a RuntimeError if no exception is given.

It’s public so it’s important to call it from the production definitions, to have the exception set to ParserError.



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# File 'lib/llip/abstract_parser.rb', line 42

def raise(*args) 
  if args.first.respond_to? :exception or not @scanner.respond_to? :current or @scanner.current == nil
    super(*args)
  else
    error = ParserError.new(@scanner.current,args.shift)
    backtrace = args.shift
    backtrace ||= caller(1)
    error.set_backtrace(backtrace)
    super error
  end
end