Class: Treetop::Compiler::Predicate

Inherits:
ParsingExpression show all
Defined in:
lib/treetop/compiler/node_classes/predicate.rb

Direct Known Subclasses

AndPredicate, NotPredicate

Instance Attribute Summary

Attributes inherited from ParsingExpression

#address, #builder, #parent_expression, #subexpression_address, #var_symbols

Attributes inherited from Runtime::SyntaxNode

#input, #interval, #parent

Instance Method Summary collapse

Methods inherited from ParsingExpression

#accumulate_subexpression_result, #accumulator_var, #assign_lazily_instantiated_node, #assign_result, #begin_comment, #declared_module_name, #decorated?, #end_comment, #epsilon_node, #extend_result, #extend_result_with_declared_module, #extend_result_with_inline_module, #init_value, #inline_module_name, #node_class_name, #obtain_new_subexpression_address, #on_one_line, #optional_arg, #reset_index, #result_var, #start_index_var, #subexpression_result_var, #subexpression_success?, #use_vars, #var, #var_initialization

Methods inherited from Runtime::SyntaxNode

#<=>, #dot_id, #elements, #empty?, #extension_modules, #initialize, #inspect, #nonterminal?, #terminal?, #text_value, #write_dot, #write_dot_file

Constructor Details

This class inherits a constructor from Treetop::Runtime::SyntaxNode

Instance Method Details

#assign_failureObject


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# File 'lib/treetop/compiler/node_classes/predicate.rb', line 15

def assign_failure
  super(start_index_var)
end

#assign_successObject


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# File 'lib/treetop/compiler/node_classes/predicate.rb', line 19

def assign_success
  reset_index
  assign_result epsilon_node
end

#compile(address, builder, parent_expression) ⇒ Object


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# File 'lib/treetop/compiler/node_classes/predicate.rb', line 4

def compile(address, builder, parent_expression)
  super
  begin_comment(parent_expression)
  use_vars :result, :start_index
  obtain_new_subexpression_address
  parent_expression.prefixed_expression.compile(subexpression_address, builder)
  builder.if__(subexpression_success?) { when_success }
  builder.else_ { when_failure }
  end_comment(parent_expression)
end