Class: Ibex::LALR::Counterexample

Inherits:
Object
  • Object
show all
Defined in:
lib/ibex/lalr/counterexample.rb

Overview

Produces shortest-path conflict witnesses using Automaton IR only.

Constant Summary collapse

DEFAULT_MAX_TOKENS =

: Integer

ConflictSearch::DEFAULT_MAX_TOKENS
DEFAULT_MAX_CONFIGURATIONS =

: Integer

ConflictSearch::DEFAULT_MAX_CONFIGURATIONS

Instance Method Summary collapse

Constructor Details

#initialize(automaton, max_tokens: DEFAULT_MAX_TOKENS, max_configurations: DEFAULT_MAX_CONFIGURATIONS) ⇒ Counterexample

Returns a new instance of Counterexample.



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# File 'lib/ibex/lalr/counterexample.rb', line 11

def initialize(automaton, max_tokens: DEFAULT_MAX_TOKENS, max_configurations: DEFAULT_MAX_CONFIGURATIONS)
  ConflictSearchLimits.validate!(max_tokens: max_tokens, max_configurations: max_configurations)
  @automaton = automaton
  @grammar = automaton.grammar
  @max_tokens = max_tokens
  @max_configurations = max_configurations
  @shortest_yields = compute_shortest_yields
end

Instance Method Details

#all ⇒ Object 



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# File 'lib/ibex/lalr/counterexample.rb', line 21

def all
  @automaton.states.flat_map do |state|
    state.conflicts.map { |conflict| build_example(state, conflict) }
  end
end

#for_conflict(state_id, conflict_index) ⇒ Object

Raises:

  • (ArgumentError) 


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# File 'lib/ibex/lalr/counterexample.rb', line 28

def for_conflict(state_id, conflict_index)
  state = @automaton.states.find { |candidate| candidate.id == state_id }
  raise ArgumentError, "unknown automaton state #{state_id}" unless state

  unless conflict_index.is_a?(Integer) && conflict_index >= 0 && conflict_index < state.conflicts.length
    raise ArgumentError, "conflict index #{conflict_index.inspect} is invalid for automaton state #{state_id}"
  end

  conflict = state.conflicts.fetch(conflict_index)
  build_example(state, conflict)
end