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[[!comment format=mdwn
username="joey"
subject="""comment 1"""
date="2016-06-02T21:10:20Z"
content="""
You can use `ensureProperty` to do this.
withMyAcc desc mkp = property' desc $ \w ->
u <- getMyAcc
ensureProperty w (mkp u)
The type of this will be somewhat more complex than the one you gave,
but it should work.
Alas a description has to be provided to withMyAcc. It cannot reuse the
description of `mkp` because to get a property that it can introspect for its
description, a User has to be provided, and the User can only be determined by
running Propellor (IO) action getMyAcc. You might be able to finesse this
by using a monoidial value and get the description of `mkp mempty`.
Or, you could do something like this to tie the knot. I don't know if this
is a good idea (it might even `<<loop>>`), but it illustrates the core
problem nicely; to get at the Info, we need a Host, but to get a Host, we
need to already know its properties.
foo :: Host
foo = host "foo.example.com" $ props
& withMyAcc (hostInfo foo) User.accountFor
"""]]
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