Class: BELParser::Parsers::AST::Node

Inherits:
AST::Node
  • Object
show all
Defined in:
lib/bel_parser/parsers/ast/node.rb

Overview

BEL application-specific AST node.

All BEL AST nodes have a basic set of properties. Additional properties may be specified by subclasses. Each class in the hierarchy describes its type through the class variable ast_type. This is equivalent to its type instance variable but the former is not used by the AST library itself.

See Also:

Class Attribute Summary collapse

Instance Attribute Summary collapse

Attributes inherited from AST::Node

#children, #hash, #type

Instance Method Summary collapse

Methods inherited from AST::Node

#==, #dup, #eql?, #inspect, #to_a, #to_ast, #to_bel, #to_s, #to_sexp

Methods included from BELParser::Parsers

#serialize

Constructor Details

#initialize(type, children = [], properties = {}) ⇒ Node

New BEL AST node.

children Optional children of node @param [Hash] properties Optional supported node properties

Supported properties - line_number -> #line_number -

character_range -> #character_range, #range_start,

{#range_end}

properties

is not a Hash

Parameters:

  • type (Symbol) —

    The node type symbol @param [Array]

Raises:

  • ArgumentError If children is not an Array or



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# File 'lib/bel_parser/parsers/ast/node.rb', line 45

def initialize(type, children = [], properties = {})
  AST.assert_is_a(Array, children, 'children')
  AST.assert_is_a(Hash, properties, 'properties')
  super(type, children, properties)
end

Class Attribute Details

.ast_type ⇒ Object (readonly)

Returns the value of attribute ast_type.



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# File 'lib/bel_parser/parsers/ast/node.rb', line 52

def ast_type
  @ast_type
end

.has_semantics ⇒ Object (readonly)

Returns the value of attribute has_semantics.



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# File 'lib/bel_parser/parsers/ast/node.rb', line 56

def has_semantics
  @has_semantics
end

Instance Attribute Details

#character_range ⇒ Object

Get the character range enclosing this AST node. It is defined as the close interval containing all the characters of this AST node.



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# File 'lib/bel_parser/parsers/ast/node.rb', line 64

def character_range
  @character_range
end

#complete ⇒ Object

Get/Set the complete property.



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# File 'lib/bel_parser/parsers/ast/node.rb', line 67

def complete
  @complete
end

#line_number ⇒ Object (readonly)

Get the line number where this AST node originates.



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# File 'lib/bel_parser/parsers/ast/node.rb', line 59

def line_number
  @line_number
end

Instance Method Details

#add_syntax_error(syntax_error) ⇒ Object

Add a syntax error to thie AST node.



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# File 'lib/bel_parser/parsers/ast/node.rb', line 75

def add_syntax_error(syntax_error)
  syntax_errors << syntax_error
end

#append(element) ⇒ Node Also known as: <<

Appends ‘element` to `children` and returns the resulting node.

Returns:



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# File 'lib/bel_parser/parsers/ast/node.rb', line 147

def append(element)
  updated(@children + [element])
end

#child(index) ⇒ Node?

Get the child at the specified index.

Parameters:

  • index (Fixnum) —

    the index to get

Returns:

  • (Node, nil) —

    the child of this node at the indicated index or nil if not present



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# File 'lib/bel_parser/parsers/ast/node.rb', line 156

def child(index)
  @children[index]
end

#children? ⇒ true, false

Get whether this node has children.

Returns:

  • (true, false) 


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# File 'lib/bel_parser/parsers/ast/node.rb', line 194

def children?
  !@children.empty?
end

#complete? ⇒ Boolean

Get whether the AST node can be considered complete.

Returns:

  • (Boolean) 


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# File 'lib/bel_parser/parsers/ast/node.rb', line 96

def complete?
  @complete
end

#concat(array) ⇒ Node Also known as: +

Concatenates ‘array` with `children` and returns the resulting node.

Returns:



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# File 'lib/bel_parser/parsers/ast/node.rb', line 138

def concat(array)
  updated(@children + array.to_a)
end

#first_child ⇒ Object

Get the child at index 0.

See Also:



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# File 'lib/bel_parser/parsers/ast/node.rb', line 162

def first_child
  child 0
end

#fourth_child ⇒ Object

Get the child at index 3.

See Also:



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# File 'lib/bel_parser/parsers/ast/node.rb', line 180

def fourth_child
  child 3
end

#freeze ⇒ Object 



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# File 'lib/bel_parser/parsers/ast/node.rb', line 116

def freeze
  # no freeze...nothing I want to be able to modify properties!
  self
end

#incomplete? ⇒ Boolean

Get whether the AST node should be considered incomplete.

Returns:

  • (Boolean) 


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# File 'lib/bel_parser/parsers/ast/node.rb', line 101

def incomplete?
  !@complete
end

#num_children ⇒ Fixnum

Get the number of children.

Returns:

  • (Fixnum) —

    the number of children



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# File 'lib/bel_parser/parsers/ast/node.rb', line 187

def num_children
  @children.size
end

#range_end ⇒ Object Also known as: range_b

Get the end of the character range enclosing this AST node.



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# File 'lib/bel_parser/parsers/ast/node.rb', line 88

def range_end
  @character_range[1]
end

#range_start ⇒ Object Also known as: range_a

Get the start of the character range enclosing this AST node.



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# File 'lib/bel_parser/parsers/ast/node.rb', line 80

def range_start
  @character_range[0]
end

#second_child ⇒ Object

Get the child at index 1.

See Also:



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# File 'lib/bel_parser/parsers/ast/node.rb', line 168

def second_child
  child 1
end

#syntax_errors ⇒ Object

Get the syntax errors for this AST node.



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# File 'lib/bel_parser/parsers/ast/node.rb', line 70

def syntax_errors
  (@syntax_errors ||= [])
end

#third_child ⇒ Object

Get the child at index 2.

See Also:



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# File 'lib/bel_parser/parsers/ast/node.rb', line 174

def third_child
  child 2
end

#traverse(&block) ⇒ Object 



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# File 'lib/bel_parser/parsers/ast/node.rb', line 105

def traverse(&block)
  if block_given?
    yield self
    children.each do |child_node|
      child_node.traverse(&block) if child_node.respond_to?(:traverse)
    end
  else
    enum_for(:traverse)
  end
end

#updated(children = nil, properties = nil) ⇒ Object 



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# File 'lib/bel_parser/parsers/ast/node.rb', line 121

def updated(children = nil, properties = nil)
  new_children   = children   || @children
  new_properties = properties || {}

  if @children == new_children && properties.nil?
    self
  elsif instance_of? Node
    original_dup.send :initialize, @type, new_children, new_properties
  else # self.is_a? Node
    original_dup.send :initialize, new_children, new_properties
  end
end