Macro for `do` block boilerplate?

General Usage
1

I often am making types that need a open / close pair, so I usually add a method allowing them to be used in a do block that automatically clean up after itself. I’m thinking about wrapping this boilerplate into a @doable macro - is there something like this already out there?

I started out by writing the docstring:

==========================

@doable function myopen(x, y)
    # construct `z`. later it should be closed with `Base.close(z)`
end

The @doable macro adds a method with a Function first argument. This form
calls the given function and closes the object within a finally block. So the
above example creates another function of the form:

function myopen(fn::Function, x, y)
    obj = myopen(x, y)
    try
        fn(obj)
    finally
        close(obj)
    end
end

which enables users to write:

myopen(4, 5) do x
    # do stuff with x
end
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