Abstract: All
monads can be combined by using the standard
category tools related to monads. Two monads
can be combined by taking their co-product.In this paper, we give a necessary and sufficient condition for
composing two monads using co-products. We
show that a given tuple (T
· R,
m,
h)is
a monad iff it is the co-product of T
and R
in a certain category of functors and
natural transformations using a string
rewriting system.
Keywords and phrases: co-product, monads, string rewriting, natural transformation, morphism.
