class Taxonifi::Splitter::Lexer

Attributes

input[R]

token_list[R]

Public Class Methods

new(input, token_list = nil) click to toggle source

# File lib/splitter/lexer.rb, line 6
def initialize(input, token_list = nil)

  raise Taxonifi::Splitter::SplitterError, "Invalid token list passed to Lexer." if (!token_list.nil? && !Taxonifi::Splitter::TOKEN_LISTS.include?(token_list)  )
  token_list = :global_token_list if token_list.nil?

  @input = input
  @token_list = token_list 
  @next_token = nil
end

Public Instance Methods

peek(token_class, token_list = nil) click to toggle source

Checks whether the next token is of the specified class.

# File lib/splitter/lexer.rb, line 17
def peek(token_class, token_list = nil)
  token = read_next_token(token_class)
  return token.class == token_class
end

pop(token_class) click to toggle source

Return (and delete) the next token from the input stream, or raise an exception if the next token is not of the given class.

# File lib/splitter/lexer.rb, line 24
def pop(token_class)
  token = read_next_token(token_class)
  @next_token = nil
  if token.class != token_class
    raise(Taxonifi::Splitter::SplitterError, "expected #{token_class.to_s} but received #{token.class.to_s} at #{@input[0..10]}...", caller)
  else
    return token
  end
end