module Gecode::SetEnum::SetEnumOperand

A SetEnumOperand is a enumeration of SetOperand on which the constraints defined in SetEnumConstraintReceiver can be placed.

Enumerations of set operands can be created either by using Gecode::Mixin#set_var_array and Gecode::Mixin#set_var_matrix, or by wrapping an existing enumeration containing SetOperand using Gecode::Mixin#wrap_enum. The enumerations, no matter how they were created, all respond to the properties defined by SetEnumOperand.

Examples ¶ ↑

Produces an array of five set operands, with greatest lower bound {0} and least upper bound {0, 1, 2}, inside a problem formulation using Gecode::Mixin#set_var_array:

set_enum = set_var_array(5, 0, 1..2)

Uses Gecode::Mixin#wrap_enum inside a problem formulation to create a SetEnumOperand from an existing enumeration containing the set operands set_operand1 and set_operand2:

set_enum = wrap_enum([set_operand1, set_operand2])

Public Instance Methods

disjoint_union() click to toggle source

Produces a SetOperand representing the disjoint union of all sets in this enumeration.

Examples ¶ ↑

# The disjoint union of all sets in +set_enum+.
set_enum.disjoint_union

# File lib/gecoder/interface/constraints/set_enum/operation.rb, line 32
def disjoint_union
  set_operation(:disjoint_union)
end

intersection() click to toggle source

Produces a SetOperand representing the intersection of all sets in this enumeration.

Examples ¶ ↑

# The intersection of all sets in +set_enum+.
set_enum.intersection

# File lib/gecoder/interface/constraints/set_enum/operation.rb, line 21
def intersection
  set_operation(:intersection)
end

union() click to toggle source

Produces a SetOperand representing the union of all sets in this enumeration.

Examples ¶ ↑

# The union of all sets in +set_enum+.
set_enum.union

# File lib/gecoder/interface/constraints/set_enum/operation.rb, line 10
def union
  set_operation(:union)
end

Public Class Methods

[](*vars) click to toggle source

Produces a SetOperand representing the i:th set operand in the enumeration, where i is the value of the int operand used as index.

A set can also be used as index, in which case a SelectedSetOperand is produced.

Examples ¶ ↑

# The set operand at the +x+:th position in +set_enum+,
# where +x+ is a int operand.  
set_enum[x]

# The SelectedSetOperand representing sets at positions
# included in the value of +set+ in +set_enum+,
set_enum[set]

# File lib/gecoder/interface/constraints/set_enum/element.rb, line 37
def [](*vars)
  # Hook in an element constraint if a operand is used for array 
  # access.
  if vars.first.respond_to? :to_int_var
    Element::ElementSetOperand.new(
      model, self, vars.first)
  elsif vars.first.respond_to? :to_set_var
    Gecode::SelectedSet::SelectedSetOperand.new(
      self, vars.first)
  else
    if respond_to? :pre_set_element_access
      pre_set_element_access(*vars) 
    end
  end
end