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instance method

BasicObject#instance_exec

obj.instance_exec(arg...) {|var...| block } → obj

static VALUE
rb_obj_instance_exec_internal(int argc, const VALUE *argv, VALUE self)
{
    VALUE klass = singleton_class_for_eval(self);
    return yield_under(klass, self, argc, argv, RB_PASS_CALLED_KEYWORDS);
}

Executes the given block within the context of the receiver (obj). In order to set the context, the variable self is set to obj while the code is executing, giving the code access to obj’s instance variables. Arguments are passed as block parameters.

Example

class KlassWithSecret
  def initialize
    @secret = 99
  end
end
k = KlassWithSecret.new
k.instance_exec(5) {|x| @secret+x }   #=> 104

See also #instance_eval #method_missing #__id__ #__send__ also in 4.1 · 4.0 · 3.4 · 3.3 · 3.2 · 3.1

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