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Please help me get all instance variables declared in a class the same way instance_methods shows me all methods available in a class.
class A attr_accessor :ab, :ac end puts A.instance_methods #gives ab and ac puts A.something #gives me @ab @ac... 
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Instance variables are declared at the same level as methods within a class definition. They are usually given private access to restrict visibility. They can receive initial values either when they are declared or in a constructor. Instances variable references may or may not be prefixed with the reserved word this.
There are two ways to access the instance variable of class: Within the class by using self and object reference. Using getattr() method.
Class methods don't need a class instance. They can't access the instance ( self ) but they have access to the class itself via cls . Static methods don't have access to cls or self . They work like regular functions but belong to the class's namespace.
You can use instance_variables:
A.instance_variables but that’s probably not what you want, since that gets the instance variables in the class A, not an instance of that class. So you probably want:
a = A.new a.instance_variables But note that just calling attr_accessor doesn’t define any instance variables (it just defines methods), so there won’t be any in the instance until you set them explicitly.
a = A.new a.instance_variables #=> [] a.ab = 'foo' a.instance_variables #=> [:@ab] If you want to get all instances variables values you can try something like this :
class A attr_accessor :foo, :bar def context self.instance_variables.map do |attribute| { attribute => self.instance_variable_get(attribute) } end end end a = A.new a.foo = "foo" a.bar = 42 a.context #=> [{ :@foo => "foo" }, { :@bar => 42 }] If you love us? You can donate to us via Paypal or buy me a coffee so we can maintain and grow! Thank you!
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