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instance method

Object#instance_variables

() -> ::Array[::Symbol]

obj.instance_variables → array

VALUE
rb_obj_instance_variables(VALUE obj)
{
    VALUE ary = rb_ary_new_capa(rb_ivar_count(obj));
    rb_ivar_foreach(obj, ivar_i, ary);
    return ary;
}

Returns an array of instance variable names for the receiver. Note that simply defining an accessor does not create the corresponding instance variable.

Example

class Fred
  attr_accessor :a1
  def initialize
    @iv = 3
  end
end
Fred.new.instance_variables   #=> [:@iv]

See also #instance_variable_get #instance_variable_set #instance_variable_defined? #is_a? also in 4.0 · 3.4 · 3.3 · 3.2 · 3.1 · 3.0

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