  Notions of computation can be modelled by monads. Algebraic effects offer a
characterization of monads in terms of algebraic operations and equational
axioms, where operations are basic programming features, such as reading or
updating the state, and axioms specify observably equivalent expressions.
However, many useful programming features depend on additional mechanisms such
as delimited scopes or dynamically allocated resources. Such mechanisms can be
supported via extensions to algebraic effects including scoped effects and
parameterized algebraic theories. We present a fresh perspective on scoped
effects by translation into a variation of parameterized algebraic theories.
The translation enables a new approach to equational reasoning for scoped
effects and gives rise to an alternative characterization of monads in terms of
generators and equations involving both scoped and algebraic operations. We
demonstrate the power of our fresh perspective by way of equational
characterizations of several known models of scoped effects.
