Haskell parse error on input ‘|’ when trying to compile -

hi i'm learning haskell , made code implemente fractions when compile error parse error on input ‘|’ code following:

module fraccion(frac,div,mcd,fraccion)   data frac = div integer integer deriving (eq, show)   mcd :: integer -> integer -> integer mcd b | > b = mcd (a-b) b         | < b = mcd (b-a)         | == b =  fraccion :: integer -> integer -> frac  fraccion b | b == 0 = error "divisor can't 0"              | b <  0 = fraccion (-a) (-b)              | b >  0 = div (a `div` mcdab) (b `div` mcdab)                         mcdab = mcd (abs a) b  instance (num frac)     negate (div b)      = (div (-a) b)     abs    (div b)      = (div (abs a) b)     (div b) * (div c d) = fraccion (a*c) (b*d)     (div b) + (div c d) = fraccion (a*d+b*c) (b*d)     (div b) - (div c d) = fraccion (a*d-b*c) (b*d)     frominteger n = (div n 1)     signum (div b) | > 0 = 1                      | < 0 + -1                      | == b = 0  instance show frac     show (div b) = (show a) ++ "/" ++ (show b) 

could please me error?

on line 27:

| < 0 + -1 

a simple typo. put + meant =

| < 0 = -1 

you'll want capitalize show on second-to-last line. deriving clause type shouldn't include show either, because define instance explicitly rather deriving it. finally, module export list should this.

module fraccion(frac(div),mcd,fraccion)