metasploit-framework/lib/enumerable.rb

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#
# This Module was developed by Thomas Hafner.
# No other references about the author.
#
# TITLE:
#
# Cartesian
#
# SUMMARY:
#
# Cartesian product and similar methods.
#
# AUTHORS:
#
# - Thomas Hafner
#
module Enumerable
class << self
# Provides the cross-product of two or more Enumerables.
# This is the class-level method. The instance method
# calls on this.
#
# Enumerable.cart([1,2], [4], ["apple", "banana"])
# #=> [[1, 4, "apple"], [1, 4, "banana"], [2, 4, "apple"], [2, 4, "banana"]]
#
# Enumerable.cart([1,2], [3,4])
# #=> [[1, 3], [1, 4], [2, 3], [2, 4]]
def cartesian_product(*enums, &block)
result = [[]]
while [] != enums
t, result = result, []
b, *enums = enums
t.each do |a|
b.each do |n|
result << a + [n]
end
end
end
if block_given?
result.each{ |e| block.call(e) }
else
result
end
end
alias_method :cart, :cartesian_product
end
# The instance level version of <tt>Enumerable::cartesian_product</tt>.
#
# a = []
# [1,2].cart([4,5]){|elem| a << elem }
# a #=> [[1, 4],[1, 5],[2, 4],[2, 5]]
def cartesian_product(*enums, &block)
Enumerable.cartesian_product(self, *enums, &block)
end
alias :cart :cartesian_product
# Operator alias for cross-product.
#
# a = [1,2] ** [4,5]
# a #=> [[1, 4],[1, 5],[2, 4],[2, 5]]
#
def **(enum)
Enumerable.cartesian_product(self, enum)
end
# Expected to be an enumeration of arrays. This method
# iterates through combinations of each in position.
#
# a = [ [0,1], [2,3] ]
# a.each_combo { |c| p c }
#
# produces
#
# [0, 2]
# [0, 3]
# [1, 2]
# [1, 3]
#
def each_combo
a = collect{ |x|
x.respond_to?(:to_a) ? x.to_a : 0..x
}
if a.size == 1
r = a.shift
r.each{ |n|
yield n
}
else
r = a.shift
r.each{ |n|
a.each_combo{ |s|
yield [n, *s]
}
}
end
end
# As with each_combo but returns combos collected in an array.
#
def combos
a = []
each_combo{ |c| a << c }
a
end
end