T5358.hs:7:1:
    The equation(s) for `t1' have one argument,
    but its type `Int' has none

T5358.hs:8:1:
    The equation(s) for `t2' have one argument,
    but its type `Int' has none

T5358.hs:10:13:
    The function `t1' is applied to one argument,
    but its type `Int' has none
    In the first argument of `(==)', namely `t1 x'
    In the expression: t1 x == t2 x
    In an equation for `prop_x1': prop_x1 x = t1 x == t2 x