I don't understand why `b(r+1) g f = \x -> b(r) g f x`. In my opinion `b(r+1) g f x = b(r+1) g f x` because eta-expansion. And `b(r+1)` should be `b(r) . (.)`, i.e. `b(r+1) g f = b(r) (g .) f` by equational reasoning. Wish someone help me to figure this out, thank everyone.
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I don't understand why `b(r+1) g f = \x -> b(r) g f x`.
In my opinion `b(r+1) g f x = b(r+1) g f x` because eta-expansion.
And `b(r+1)` should be `b(r) . (.)`, i.e. `b(r+1) g f = b(r) (g .) f` by equational reasoning.
Wish someone help me to figure this out, thank everyone.