... language¹

Historically, homomorphisms are closely connected to syntax-directed translations [1] and correspond to compositional definitions [9].

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... only²

Languages with multi-dispatch, e.g., CLOS , Cecil , or Dylan  are not in widespread use.

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... respectively³

As is the case with all generic functions of figure 4.

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... generic⁴

This time generic means (static) parametric polymorphism, whereas we imply (dynamic) inclusion polymorphism in case of generic functions.

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...pretty_functions)⁵

It is easy to shield the client from the existence of function packages, by providing a tailored generic function that creates a standard generic function with a fixed function package (e.g., pretty_functions).

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... package)⁶

At this point a runtime error may occur due to a missing specialized function. Some exception handling or other kinds of gracefully dealing with such a situation would be appropriate.

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