Class: Prism::Compiler

Inherits:

Object

Object
Prism::Compiler

show all

Defined in:: lib/prism/compiler.rb

Overview

A compiler is a visitor that returns the value of each node as it visits. This is as opposed to a visitor which will only walk the tree. This can be useful when you are trying to compile a tree into a different format.

For example, to build a representation of the tree as s-expressions, you could write:

class SExpressions < Prism::Compiler
  def visit_arguments_node(node) = [:arguments, super]
  def visit_call_node(node) = [:call, super]
  def visit_integer_node(node) = [:integer]
  def visit_program_node(node) = [:program, super]
end

Prism.parse("1 + 2").value.accept(SExpressions.new)
# => [:program, [[[:call, [[:integer], [:arguments, [[:integer]]]]]]]]

Direct Known Subclasses

MutationCompiler

Instance Method Summary collapse

#visit(node) ⇒ Object

Visit an individual node.
#visit_all(nodes) ⇒ Object

Visit a list of nodes.
#visit_child_nodes(node) ⇒ Object (also: #visit_alias_global_variable_node, #visit_alias_method_node, #visit_alternation_pattern_node, #visit_and_node, #visit_arguments_node, #visit_array_node, #visit_array_pattern_node, #visit_assoc_node, #visit_assoc_splat_node, #visit_back_reference_read_node, #visit_begin_node, #visit_block_argument_node, #visit_block_local_variable_node, #visit_block_node, #visit_block_parameter_node, #visit_block_parameters_node, #visit_break_node, #visit_call_and_write_node, #visit_call_node, #visit_call_operator_write_node, #visit_call_or_write_node, #visit_call_target_node, #visit_capture_pattern_node, #visit_case_match_node, #visit_case_node, #visit_class_node, #visit_class_variable_and_write_node, #visit_class_variable_operator_write_node, #visit_class_variable_or_write_node, #visit_class_variable_read_node, #visit_class_variable_target_node, #visit_class_variable_write_node, #visit_constant_and_write_node, #visit_constant_operator_write_node, #visit_constant_or_write_node, #visit_constant_path_and_write_node, #visit_constant_path_node, #visit_constant_path_operator_write_node, #visit_constant_path_or_write_node, #visit_constant_path_target_node, #visit_constant_path_write_node, #visit_constant_read_node, #visit_constant_target_node, #visit_constant_write_node, #visit_def_node, #visit_defined_node, #visit_else_node, #visit_embedded_statements_node, #visit_embedded_variable_node, #visit_ensure_node, #visit_false_node, #visit_find_pattern_node, #visit_flip_flop_node, #visit_float_node, #visit_for_node, #visit_forwarding_arguments_node, #visit_forwarding_parameter_node, #visit_forwarding_super_node, #visit_global_variable_and_write_node, #visit_global_variable_operator_write_node, #visit_global_variable_or_write_node, #visit_global_variable_read_node, #visit_global_variable_target_node, #visit_global_variable_write_node, #visit_hash_node, #visit_hash_pattern_node, #visit_if_node, #visit_imaginary_node, #visit_implicit_node, #visit_implicit_rest_node, #visit_in_node, #visit_index_and_write_node, #visit_index_operator_write_node, #visit_index_or_write_node, #visit_index_target_node, #visit_instance_variable_and_write_node, #visit_instance_variable_operator_write_node, #visit_instance_variable_or_write_node, #visit_instance_variable_read_node, #visit_instance_variable_target_node, #visit_instance_variable_write_node, #visit_integer_node, #visit_interpolated_match_last_line_node, #visit_interpolated_regular_expression_node, #visit_interpolated_string_node, #visit_interpolated_symbol_node, #visit_interpolated_x_string_node, #visit_keyword_hash_node, #visit_keyword_rest_parameter_node, #visit_lambda_node, #visit_local_variable_and_write_node, #visit_local_variable_operator_write_node, #visit_local_variable_or_write_node, #visit_local_variable_read_node, #visit_local_variable_target_node, #visit_local_variable_write_node, #visit_match_last_line_node, #visit_match_predicate_node, #visit_match_required_node, #visit_match_write_node, #visit_missing_node, #visit_module_node, #visit_multi_target_node, #visit_multi_write_node, #visit_next_node, #visit_nil_node, #visit_no_keywords_parameter_node, #visit_numbered_parameters_node, #visit_numbered_reference_read_node, #visit_optional_keyword_parameter_node, #visit_optional_parameter_node, #visit_or_node, #visit_parameters_node, #visit_parentheses_node, #visit_pinned_expression_node, #visit_pinned_variable_node, #visit_post_execution_node, #visit_pre_execution_node, #visit_program_node, #visit_range_node, #visit_rational_node, #visit_redo_node, #visit_regular_expression_node, #visit_required_keyword_parameter_node, #visit_required_parameter_node, #visit_rescue_modifier_node, #visit_rescue_node, #visit_rest_parameter_node, #visit_retry_node, #visit_return_node, #visit_self_node, #visit_singleton_class_node, #visit_source_encoding_node, #visit_source_file_node, #visit_source_line_node, #visit_splat_node, #visit_statements_node, #visit_string_node, #visit_super_node, #visit_symbol_node, #visit_true_node, #visit_undef_node, #visit_unless_node, #visit_until_node, #visit_when_node, #visit_while_node, #visit_x_string_node, #visit_yield_node)

Visit the child nodes of the given node.

Instance Method Details

#visit(node) ⇒ `Object`

Visit an individual node.



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# File 'lib/prism/compiler.rb', line 28

def visit(node)
  node&.accept(self)
end

#visit_all(nodes) ⇒ `Object`

Visit a list of nodes.



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# File 'lib/prism/compiler.rb', line 33

def visit_all(nodes)
  nodes.map { |node| node&.accept(self) }
end

#visit_child_nodes(node) ⇒ `Object` Also known as: visit_alias_global_variable_node, visit_alias_method_node, visit_alternation_pattern_node, visit_and_node, visit_arguments_node, visit_array_node, visit_array_pattern_node, visit_assoc_node, visit_assoc_splat_node, visit_back_reference_read_node, visit_begin_node, visit_block_argument_node, visit_block_local_variable_node, visit_block_node, visit_block_parameter_node, visit_block_parameters_node, visit_break_node, visit_call_and_write_node, visit_call_node, visit_call_operator_write_node, visit_call_or_write_node, visit_call_target_node, visit_capture_pattern_node, visit_case_match_node, visit_case_node, visit_class_node, visit_class_variable_and_write_node, visit_class_variable_operator_write_node, visit_class_variable_or_write_node, visit_class_variable_read_node, visit_class_variable_target_node, visit_class_variable_write_node, visit_constant_and_write_node, visit_constant_operator_write_node, visit_constant_or_write_node, visit_constant_path_and_write_node, visit_constant_path_node, visit_constant_path_operator_write_node, visit_constant_path_or_write_node, visit_constant_path_target_node, visit_constant_path_write_node, visit_constant_read_node, visit_constant_target_node, visit_constant_write_node, visit_def_node, visit_defined_node, visit_else_node, visit_embedded_statements_node, visit_embedded_variable_node, visit_ensure_node, visit_false_node, visit_find_pattern_node, visit_flip_flop_node, visit_float_node, visit_for_node, visit_forwarding_arguments_node, visit_forwarding_parameter_node, visit_forwarding_super_node, visit_global_variable_and_write_node, visit_global_variable_operator_write_node, visit_global_variable_or_write_node, visit_global_variable_read_node, visit_global_variable_target_node, visit_global_variable_write_node, visit_hash_node, visit_hash_pattern_node, visit_if_node, visit_imaginary_node, visit_implicit_node, visit_implicit_rest_node, visit_in_node, visit_index_and_write_node, visit_index_operator_write_node, visit_index_or_write_node, visit_index_target_node, visit_instance_variable_and_write_node, visit_instance_variable_operator_write_node, visit_instance_variable_or_write_node, visit_instance_variable_read_node, visit_instance_variable_target_node, visit_instance_variable_write_node, visit_integer_node, visit_interpolated_match_last_line_node, visit_interpolated_regular_expression_node, visit_interpolated_string_node, visit_interpolated_symbol_node, visit_interpolated_x_string_node, visit_keyword_hash_node, visit_keyword_rest_parameter_node, visit_lambda_node, visit_local_variable_and_write_node, visit_local_variable_operator_write_node, visit_local_variable_or_write_node, visit_local_variable_read_node, visit_local_variable_target_node, visit_local_variable_write_node, visit_match_last_line_node, visit_match_predicate_node, visit_match_required_node, visit_match_write_node, visit_missing_node, visit_module_node, visit_multi_target_node, visit_multi_write_node, visit_next_node, visit_nil_node, visit_no_keywords_parameter_node, visit_numbered_parameters_node, visit_numbered_reference_read_node, visit_optional_keyword_parameter_node, visit_optional_parameter_node, visit_or_node, visit_parameters_node, visit_parentheses_node, visit_pinned_expression_node, visit_pinned_variable_node, visit_post_execution_node, visit_pre_execution_node, visit_program_node, visit_range_node, visit_rational_node, visit_redo_node, visit_regular_expression_node, visit_required_keyword_parameter_node, visit_required_parameter_node, visit_rescue_modifier_node, visit_rescue_node, visit_rest_parameter_node, visit_retry_node, visit_return_node, visit_self_node, visit_singleton_class_node, visit_source_encoding_node, visit_source_file_node, visit_source_line_node, visit_splat_node, visit_statements_node, visit_string_node, visit_super_node, visit_symbol_node, visit_true_node, visit_undef_node, visit_unless_node, visit_until_node, visit_when_node, visit_while_node, visit_x_string_node, visit_yield_node

Visit the child nodes of the given node.



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# File 'lib/prism/compiler.rb', line 38

def visit_child_nodes(node)
  node.compact_child_nodes.map { |node| node.accept(self) }
end