Class: Arel::Predicates::Unary

Inherits:
Predicate show all
Defined in:
lib/arel/algebra/predicates.rb

Direct Known Subclasses

Binary, Not

Instance Attribute Summary collapse

Instance Method Summary collapse

Methods inherited from Predicate

#and, #complement, #not, #or

Constructor Details

#initialize(operand) ⇒ Unary

Returns a new instance of Unary.



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# File 'lib/arel/algebra/predicates.rb', line 87

def initialize operand
  @operand = operand
end

Instance Attribute Details

#operand ⇒ Object (readonly)

Returns the value of attribute operand.



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# File 'lib/arel/algebra/predicates.rb', line 85

def operand
  @operand
end

Instance Method Details

#==(other) ⇒ Object 



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# File 'lib/arel/algebra/predicates.rb', line 95

def == other
  super || self.class === other && operand == other.operand
end

#bind(relation) ⇒ Object 



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# File 'lib/arel/algebra/predicates.rb', line 91

def bind(relation)
  self.class.new(operand.find_correlate_in(relation))
end

#eval(row) ⇒ Object 



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# File 'lib/arel/algebra/predicates.rb', line 99

def eval(row)
  operand.eval(row).send(operator)
end

#to_sql(formatter = nil) ⇒ Object 



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# File 'lib/arel/algebra/predicates.rb', line 103

def to_sql(formatter = nil)
  "#{predicate_sql} (#{operand.to_sql(formatter)})"
end