[Haskell-cafe] about beta NF in lambda calculus

[Algebras Math]

hi,

What is the different between 'in beta normal form' and 'has beta normal
form' ? Does the former means the current form of the term is already in
normal form but the latter means that it is not a normal form yet and can be
reduced to be normal form? Like  \x.x is in NF and (\x.x) (\x.x) has NF?

If above is true, I am confused why we have to distinguish the terms which
have NF and be in NF? isn't the terms have NF will eventually become in NF?
or there are some way to avoid them becoming in NF?

Thanks

Alg
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