Module: Alf::Algebra::Operator

Extended by:
Support::Registry
Includes:
Operand
Included in:
Autonum, Clip, Coerce, Compact, Defaults, Extend, Generator, Group, InferHeading, Intersect, Join, Matching, Minus, NotMatching, Project, Quota, Rank, Rename, Restrict, Sort, Summarize, TypeSafe, Ungroup, Union, Unwrap, Wrap
Defined in:
lib/alf-algebra/alf/algebra/operator.rb

Defined Under Namespace

Modules: ClassMethods

Instance Attribute Summary collapse

Attributes included from Support::Bindable

#connection

Class Method Summary collapse

Instance Method Summary collapse

Methods included from Support::Registry

each, listen, listeners, register, registered

Methods included from Operand

#attr_list, coerce, #heading, #keys, #to_cog, #to_dot, #to_relation

Methods included from Support::Bindable

#bound?, #connection!

Instance Attribute Details

#operands ⇒ Object

Parameters:

  • operands (Array) —

    Operator operands



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# File 'lib/alf-algebra/alf/algebra/operator.rb', line 44

def operands
  @operands
end

Class Method Details

.included(mod) ⇒ Object

Installs the class methods needed on all operators



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# File 'lib/alf-algebra/alf/algebra/operator.rb', line 33

def included(mod)
  super
  mod.extend(ClassMethods)
  mod.extend(Classification)
  register(mod, Operator)
end

Instance Method Details

#==(other) ⇒ Object 



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# File 'lib/alf-algebra/alf/algebra/operator.rb', line 89

def ==(other)
  (other.object_id == self.object_id) ||
  ((other.class == self.class) &&
   (other.operands == self.operands) &&
   (other.signature.collect_on(self) == self.signature.collect_on(self)))
end

#bind(connection) ⇒ Object

Binds to a connection



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# File 'lib/alf-algebra/alf/algebra/operator.rb', line 52

def bind(connection)
  super{|c| c.operands = operands.map{|op| op.bind(connection) } }
end

#dup(&bl) ⇒ Object 



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# File 'lib/alf-algebra/alf/algebra/operator.rb', line 85

def dup(&bl)
  bl.nil? ? super : super.tap(&bl)
end

#initialize(*args) ⇒ Object

Create an operator instance



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# File 'lib/alf-algebra/alf/algebra/operator.rb', line 47

def initialize(*args)
  signature.parse_args(args, self)
end

#signature ⇒ Signature

Returns the operator signature.

Returns:



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# File 'lib/alf-algebra/alf/algebra/operator.rb', line 57

def signature
  self.class.signature
end

#to_lispy ⇒ Object Also known as: to_s

-> to_xxx



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# File 'lib/alf-algebra/alf/algebra/operator.rb', line 63

def to_lispy
  cmdname  = self.class.rubycase_name
  oper, args, opts = signature.collect_on(self)
  args = opts.empty? ? (oper + args) : (oper + args + [ opts ])
  args = args.map{|arg| Support.to_lispy(arg) }
  "#{cmdname}(#{args.join(', ')})"
end

#to_relvar ⇒ Object 



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# File 'lib/alf-algebra/alf/algebra/operator.rb', line 72

def to_relvar
  Relvar::Virtual.new(self, connection)
end

#with_operands(*operands) ⇒ Object

identity and pseudo-mutability



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# File 'lib/alf-algebra/alf/algebra/operator.rb', line 78

def with_operands(*operands)
  dup{|copy|
    copy.operands = operands
    copy.clean_computed_attributes!
  }
end