Leftmost outermost Reduction (Haskell) -


i got task use leftmost outermost reduction on following expression:

f inc expo 9 (f (*2) expo 3 1)

inc defined as:

 inc :: int -> int  inc x = x+1

expo defined as:

expo :: int -> int expo x = expo (x*2)

and f as:

f :: (int->int) -> (int-> int) -> int -> int -> int f g h b = g(a-b)

i have absolutely no clue start reduction more functions. read hint redex not contained in other redexes, dont ;(.

i appreciate every tip/help.

the first (leftmost, outermost) reduction for

f inc expo 9 (f (*2) expo 3 1)

is apply definition of f, once, f g h b = g(a-b) use g inc, a 9 , b (f (*2) expo 3 1), giving

inc(9 - (f (*2) expo 3 1))

now we're done question asked. that's leftmost, outermost reduction made. notice didn't need use facts other functions, hint getting at.


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