Clojurians Log v2

Is this an xyproblem? What are you trying to achieve?

that sounds like a valid usecase for things like disallowing deprecated keys, or as assistance when refactoring

you could also use [:and [:map ...] [:not [:map ...]]]

or, you could use an optional key with a never-valid schema

user=> (def exclude-keys
  [:map
   [:x :int]
   [:y {:optional true} [:fn {:error/message {:en "disallowed key!"}} (constantly false)]]])
#'user/exclude-keys
user=> (m/validate exclude-keys {:x 1})
true
user=> (m/validate exclude-keys {:x 1 :y true})
false
user=> (m/validate exclude-keys {:x 1 :whatever true})
true
user=> (me/humanize (m/explain exclude-keys {:x 1 :y true}))
{:y ["disallowed key!"]}

We might already have a better name for [:fn (constantly false)] but I don't remember what it is 😅

an [:not :any]

[:and ...] and [:fn ...]?