[Haskell-beginners] Lazy evaluation, trying to find out when its done

[Lai Boon Hui]

Hi all,

I understand that the take method will evaluate the value inside the cons
cell whereas length will just evaluate the spine or structure of the list

λ> let y = "abc"
Prelude|
y :: [Char]
λ> :sprint y
y = _
λ> take 1 y
"a"
it :: [Char]
λ> :sprint y
y = 'a' : _
λ>

Well and good but why doesn't the same work on a list of Nums??

λ> let x = [1,2,3]
Prelude|
x :: Num t => [t]
λ> :sprint x
x = _
λ> take 1 x
[1]
it :: Num a => [a]
λ> :sprint x
x = _
λ>

I expected to see x = 1 : _

-- 
Best Regards,
Boon Hui
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