Class: Janeway::AST::BinaryOperator

Inherits:
Expression show all
Defined in:
lib/janeway/ast/binary_operator.rb

Overview

AST node for binary operators:

== != <= >= < > || &&

Constant Summary collapse

OPERATOR_META =

Single source of truth for what binary operators exist and how they render / classify. Adding a new operator here fills both call sites.

{
  and: { str: '&&', type: :logical },
  or: { str: '||', type: :logical },
  equal: { str: '==', type: :comparison },
  not_equal: { str: '!=', type: :comparison },
  less_than: { str: '<', type: :comparison },
  less_than_or_equal: { str: '<=', type: :comparison },
  greater_than: { str: '>', type: :comparison },
  greater_than_or_equal: { str: '>=', type: :comparison },
}.freeze

Instance Attribute Summary collapse

Attributes inherited from Expression

#next, #value

Instance Method Summary collapse

Methods inherited from Expression

#chain_of?, #indented, #literal?, #singular_query?, #type, type_name

Constructor Details

#initialize(operator, left = nil, right = nil) ⇒ BinaryOperator

Returns a new instance of BinaryOperator.

Raises:

  • (ArgumentError) 


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# File 'lib/janeway/ast/binary_operator.rb', line 11

def initialize(operator, left = nil, right = nil)
  super(nil)
  raise ArgumentError, "expect symbol, got #{operator.inspect}" unless operator.is_a?(Symbol)

  @name = operator # eg. :equal
  @left = left
  @right = right
end

Instance Attribute Details

#left ⇒ Object

Returns the value of attribute left.



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# File 'lib/janeway/ast/binary_operator.rb', line 9

def left
  @left
end

#name ⇒ Object (readonly)

Returns the value of attribute name.



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# File 'lib/janeway/ast/binary_operator.rb', line 8

def name
  @name
end

#right ⇒ Object

Returns the value of attribute right.



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# File 'lib/janeway/ast/binary_operator.rb', line 9

def right
  @right
end

Instance Method Details

#comparison_operator? ⇒ Boolean

True if this operator is a comparison operator

Returns:



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# File 'lib/janeway/ast/binary_operator.rb', line 52

def comparison_operator?
  operator_type == :comparison
end

#logical_operator? ⇒ Boolean

True if this operator is a logical operator

Returns:



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# File 'lib/janeway/ast/binary_operator.rb', line 58

def logical_operator?
  operator_type == :logical
end

#to_s ⇒ Object 



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# File 'lib/janeway/ast/binary_operator.rb', line 35

def to_s
  # Make precedence explicit by adding parentheses
  "(#{@left} #{operator_to_s} #{@right})"
end

#tree(level) ⇒ Array

Parameters:

  • level (Integer)

Returns:

  • (Array) 


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# File 'lib/janeway/ast/binary_operator.rb', line 42

def tree(level)
  [
    indented(level, to_s),
    @left.tree(level + 1),
    @right.tree(level + 1),
  ]
end

#validate! ⇒ Object

Validate the currently-set left and right operands as a well-formed binary expression. Called by the parser once both sides are assigned — the previous per-setter validation was order-dependent (left= couldn't see right and vice-versa) and missed the both-literal case when the parser assigned left first.

Raises:



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# File 'lib/janeway/ast/binary_operator.rb', line 27

def validate!
  raise Error, 'BinaryOperator requires both left and right' unless @left && @right

  validate_side(@left)
  validate_side(@right)
  validate_pair
end