haskell - It works when loaded from file, but not when typed into ghci. Why? -


if put following 2 lines foobar.hs

f 1 = 1 f x = f (x-1)

then

$ ghci > :load foobar.hs > f 5 1

but if do

$ ghci > let f 1 = 1 > let f x = f (x-1) > f 5 ^cinterrupted.

then not return. why?

the latter binding overrides former. use in ghci:

prelude> :{ prelude| let f 1 = 1 prelude|     f x = f (x-1) prelude| :} prelude> f 5 1

or, without layout:

prelude> let f 1 = 1; f x = f (x-1) prelude> f 5 1

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