# Is there a Julian way to combine types generically or a design pattern that achieves the goal?

**URL:** <https://discourse.julialang.org/t/is-there-a-julian-way-to-combine-types-generically-or-a-design-pattern-that-achieves-the-goal/983>\
**Category:** General Usage\
**Tags:** question, design-pattern\
**Created:** [December 15, 2016, 10:52pm UTC](https://discourse.julialang.org/t/is-there-a-julian-way-to-combine-types-generically-or-a-design-pattern-that-achieves-the-goal/983 "2016-12-15T22:52:30Z")\
**Posts on this page:** 1\
**Showing post:** 9

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**Author:** ![MikeInnes](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/mikeinnes/32/3656_2.png) [@MikeInnes](https://discourse.julialang.org/u/MikeInnes)\
**Post date:** [December 16, 2016, 11:14am UTC](https://discourse.julialang.org/t/is-there-a-julian-way-to-combine-types-generically-or-a-design-pattern-that-achieves-the-goal/983/9 "2016-12-16T11:14:17Z")

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Perhaps you saw this in one of the linked threads and didn’t find it a good solution for some other reason, but FWIW in this case I would just do:

```julia
type Person # ...

name(p::Person) = p.name
setname!(p::Person, name) = (p.name = name)
greet(p::Person) = println("Hello, $(name(p))")

type PersonAndAddress
  person::Person
  # ...

@forward PersonAndAddress.person name, setname!, greet

type Employee # ...

@forward Employee.person_and_address name, setname!, greet
@forward Employee.seniority_level seniority, setseniority! # etc

```

`@forward` isn’t doing anything particularly crazy or magical here, just defining the set of methods like `greet(p::PersonAndAddress, args...) = greet(p.person, args...)`. I’ve been pretty happy with this solution and haven’t found a great need for anything fancier, but if you were really working with a lot of functions you could easily generalise this to groups, e.g. (heavily cut down for brevity)

```julia
personprotocol = [name, setname!, greet]

@forward Employee.person_and_address personprotocol

employeeprotocol = [personprotocol, fire!]

@forward SeniorEmployee.employee employeeprotocol

```

I think that would would be enough to make your example – and more extreme versions of it – manageable, but let me know if that’s not the case.

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_[View the full topic](https://discourse.julialang.org/t/is-there-a-julian-way-to-combine-types-generically-or-a-design-pattern-that-achieves-the-goal/983)._