Class: OedipusLex::Group

Inherits:
Struct
  • Object
show all
Defined in:
lib/oedipus_lex.rb

Overview

A group allows you to group up multiple rules under a single regular prefix expression, allowing optimized code to be generated that skips over all actions if the prefix isn’t matched.

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(start) ⇒ Group

:nodoc:



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# File 'lib/oedipus_lex.rb', line 189

def initialize start # :nodoc:
  super(start, [])
end

Instance Attribute Details

#regex ⇒ Object Also known as: start_state

Returns the value of attribute regex

Returns:

  • (Object) —

    the current value of regex



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# File 'lib/oedipus_lex.rb', line 176

def regex
  @regex
end

#rules ⇒ Object

Returns the value of attribute rules

Returns:

  • (Object) —

    the current value of rules



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# File 'lib/oedipus_lex.rb', line 176

def rules
  @rules
end

Class Method Details

.[](start, *subrules) ⇒ Object

A convenience method to create a new group with a start and given subrules.



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# File 'lib/oedipus_lex.rb', line 183

def self.[] start, *subrules
  r = new start.inspect
  r.rules.concat subrules
  r
end

Instance Method Details

#<<(rule) ⇒ Object

Add a rule to this group.



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# File 'lib/oedipus_lex.rb', line 196

def << rule
  rules << rule
  nil
end

#pretty_print(pp) ⇒ Object

:nodoc:



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# File 'lib/oedipus_lex.rb', line 213

def pretty_print pp # :nodoc:
  pp.text "Group"
  pp.group 2, "[", "]" do
    pp.seplist([regex] + rules, lambda { pp.comma_breakable }, :each) { |v|
      pp.send(String === v ? :text : :pp, v)
    }
  end
end

#to_ruby(state, predicates, exclusive) ⇒ Object

:nodoc:



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# File 'lib/oedipus_lex.rb', line 201

def to_ruby state, predicates, exclusive # :nodoc:
  [
   "when ss.match?(#{regex}) then",
   "  case",
   rules.map { |subrule|
     s = subrule.to_ruby(state, predicates, exclusive)
     s && s.join("\n").gsub(/^/, "  ")
   }.compact,
   "  end # group #{regex}"
  ]
end