Method: Module#-

Defined in:
lib/core/facets/module/op.rb

#-(other) ⇒ Object

Subtract modules.

module AMinus
  def a; "a"; end
  def b; "b"; end
end

CMinus = AMinus - [:a]

class XMinus; include CMinus; end

expect NameError do
  XMinus.new.a  #=> "a"
end

XMinus.new.b    #=> "b"

TODO: Should this use all instance methods, not just public?

CREDIT: Thomas Sawyer, Robert Dober



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# File 'lib/core/facets/module/op.rb', line 64

def -(other)
  instance_methods = instance_methods(true).map{|m| m.to_sym}
  case other
  when Array
    subtract = instance_methods & other.map{|m| m.to_sym}
  when Module
    subtract = instance_methods & other.instance_methods(true).map{|m| m.to_sym}  # false?
  when String, Symbol
    subtract = instance_methods & [other.to_sym]
  end
  base = self
  Module.new do
    include base
    subtract.each{ |x| undef_method x }
  end
end