[Haskell-beginners] Dependent and independent variables in foldl and foldr

[Lawrence Bottorff]

I have this

myLength1 = foldl (\n _ -> n + 1) 0

and this

myLength2 = foldr (\_ n -> n + 1) 0

I am guessing that foldl knows to assign the accumulator-seed argument to
the dependent variable and the list argument's elements recursively to the
independent variable; and with foldr to do the opposite. Is this a fair
assumption? BTW, where can I get a look at the code for fold functions; or
does the type definition answer my original question? Not really able to
decipher it so well

 :t foldl
foldl :: Foldable t => (b -> a -> b) -> b -> t a -> b

LB
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